November 2022 - mice-discuss - lists.micemn.net

Re: [EXTERNAL] Re: [MICE-DISCUSS] Proposal: MICE Static MAC address Only

by Jeremy Lumby

I think the way to think about it was the damage was done in 2 seconds (according to the syslog), however the switch did not automatically recover from those 2 seconds. So we need a method that will react quicker than 2 seconds like a MAC ACL. From: MICE Discuss [mailto:MICE-DISCUSS@LISTS.IPHOUSE.NET] On Behalf Of Tom Krenn Sent: Wednesday, November 02, 2022 4:24 PM To: MICE-DISCUSS(a)LISTS.IPHOUSE.NET Subject: Re: [MICE-DISCUSS] [EXTERNAL] Re: [MICE-DISCUSS] Proposal: MICE Static MAC address Only I don't know the config of the switch but out of curiosity, would storm control help mitigate the impact on the forwarding table? We might still have 2-3 seconds of disruption but it may avoid the manual intervention and let us keep the more dynamic port security approach. Tom Krenn Network Architect Enterprise Architecture - Information Technology From: MICE Discuss <MICE-DISCUSS(a)LISTS.IPHOUSE.NET> On Behalf Of Jeremy Lumby Sent: Monday, October 31, 2022 9:12 AM To: MICE-DISCUSS(a)LISTS.IPHOUSE.NET Subject: Re: [MICE-DISCUSS] [EXTERNAL] Re: [MICE-DISCUSS] Proposal: MICE Static MAC address Only The issue was a member port. The port security took 2 seconds to shutdown the port, however 100G of traffic looped and crashed the forwarding table on the main switch, forcing manual intervention. A static MAC ACL on each port would not have taken time to react. This is what the SIX has been doing on their ports since 2010 (as well as multiple other layers of security). From: MICE Discuss [mailto:MICE-DISCUSS@LISTS.IPHOUSE.NET <MICE-DISCUSS(a)LISTS.IPHOUSE.NET>] On Behalf Of Kittel, Brady Sent: Monday, October 31, 2022 9:07 AM To:MICE-DISCUSS@LISTS.IPHOUSE.NET Subject: Re: [MICE-DISCUSS] [EXTERNAL] Re: [MICE-DISCUSS] Proposal: MICE Static MAC address Only Was the source of the issue a remote switch? " To be clear, this is still only for end ports, not ports facing remoteswitches, of course. The remote switches are responsible for enforcingthe current MAC limit, and would be responsible for changing thosesettings as described here." -Brady ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- From: MICE Discuss <MICE-DISCUSS(a)LISTS.IPHOUSE.NET> on behalf of Jay Hanke <jayhanke(a)SOUTHFRONT.IO> Sent: Monday, October 31, 2022 9:05:08 AM To:MICE-DISCUSS@LISTS.IPHOUSE.NET <MICE-DISCUSS(a)LISTS.IPHOUSE.NET> Subject: [EXTERNAL] Re: [MICE-DISCUSS] Proposal: MICE Static MAC address Only CAUTION: This email originated from outside of HCMC. DO NOT CLICK links or open attachments unless you recognize the sender and know the content is safe. The error disable takes 1-2 seconds to clamp down and disable the port. This results in a short, but severe, broadcast storm. The churn rate on members changing mac addresses is fairly low. I agree that we should automate the process so it can be done via self-service by the members. On Mon, Oct 31, 2022 at 8:59 AM Steve Howard <showard(a)paulbunyan.net> wrote: > > > Below is a message indicating the current policy as decided by the MICE Board in December 2019 is that the MAC address limit is 1. > > > The subject of Jay's message indicates "Static" MAC, but, the text seems to indicate a limit of 1. I like the 1 address limit, but, am not a fan of Static. Was the current issue caused by somebody not having a proper MAC address limit installed? > > > On 12/13/19 18:00, Richard Laager wrote: > > The board has approved the change in MAC address limit from 5 to 1. > > NOTE: This is orthogonal to the dedicated remote switch question, which > is still pending. Non-dedicated remote switches can, for example, > enforce this per-VLAN. > > We have already confirmed that most participants are using only 1 MAC > address, and some that were using more than 1 have addressed that after > being contacted. As discussed below, this change will be rolled out in a > way to keep everyone working, by grandfathering if necessary. > > On 10/28/19 3:25 PM, Richard Laager wrote: > > We have discussed this a bit in the past, and this came up at the last > UG. I'm looking for feedback from the group before formally proposing > this to the board for a vote. > > I first brought this up to the technical committee, CCing the board. I > have heard no objections. Jeremy is "in favor of it 100%". > > Based on our quick conversation after the UG, I _think_ Anthony is in > favor as well; we both made notes to follow up on this. > > ----- > > I am proposing that MICE change its MAC address limit from 5 MACs per > port to 1 MAC per port. 1 MAC address is enough for normal scenarios and > this would further limit the potential for problems on the fabric. This > restriction is one that SIX and AMS-IX both have, with the latter being > known for their excellent configuration guide for participants: >https://nam02.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.ams-i… <https://gcc02.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.ams-i…> > > To be clear, this is still only for end ports, not ports facing remote > switches, of course. The remote switches are responsible for enforcing > the current MAC limit, and would be responsible for changing those > settings as described here. > > If someone is swapping their MICE-facing router, the resulting port flap > on the MICE/remote switch will clear the limit anyway, if they are > directly connected. If they are unable to flap the port (e.g. because > they have someone else's layer 2 gear in the middle), they will have to > either work with that carrier or their switch operator (MICE/remote) to > flap the port. This is a non-zero burden, but I think it's pretty > minimal in practice. Additionally, if someone plans to make an equipment > swap, we would increase the limit in advance, temporarily, upon request. > > For reference, SIX goes further and locks you to a particular MAC > address in an ACL, so you have to contact them to change your MAC. I am > not proposing that. Still, I've been through that a couple of times, and > even that isn't really too big of a deal. So I don't think the change to > a limit of 1 MAC at MICE will be particularly onerous. > > There are a couple of participants who have two IP address sets (one > IPv4 and one IPv6) on the same port. For those ports, the limit > obviously must be at least 2 MACs, but I propose 3 MACs as the limit. If > they're using two IPs, they probably are doing so to get some redundancy > out of it. For this particular use case, needing to flap the port > defeats that redundancy goal, as it breaks the other router. Having a > MAC limit of 3 would allow them to swap a device without needing to flap > the port. We would grandfather these setups until they are looking for a > port-type upgrade; at that point they would need to get to one IP > address set per port (by splitting into two ports or reducing to one IP > address set) or request an exception as outlined below. The exception > process would allow us to better evaluate this use case at that time. > > There are some members who have multiple MACs showing up now, despite > using only one device. For those, I am proposing we set the MAC limit to > however many MACs are currently showing up on their port. That is, they > would be grandfathered at their current situation for now. At the time > of this change, we would encourage them to investigate and fix the > multiple MACs issue at their leisure. In the future, if they are doing a > equipment swap (especially like-for-like), we would again encourage them > to address it, but would otherwise leave their higher limit in place. If > they do a port-type upgrade, we would not bring the grandfathering over. > If they needed, they could ask for an official exception at that time. > > There may be cases where people cannot reasonably fix their routers to > use only 1 MAC, other scenarios I haven't considered, or things that may > come up in the future. For that reason, I think we should allow for the > possibility of exceptions upon request to the board. In practice, I > would expect the board would confer with the technical committee and/or > the technical committee would be bringing these to the board anyway. The > goal is to strike a reasonable balance between protecting the fabric > without preventing networks from connecting. > > > > > On 10/31/22 08:27, Jay Hanke wrote: > > I propose we change the MICE required port security settings to be > hard filtered for a single static mac address per port. > > Over the years, we've had several incidents where floods have occurred > prior to port being error-disabled during a looping event. > > > > ________________________________ > > To unsubscribe from the MICE-DISCUSS list, click the following link: >https://nam02.safelinks.protection.outlook.com/?url=http%3A%2F%2Flists.ipho… <https://gcc02.safelinks.protection.outlook.com/?url=http%3A%2F%2Flists.ipho…> -- Jay Hanke, President South Front Networks jayhanke(a)southfront.io Phone 612-204-0000 Confidentiality Notice: Information contained in this e-mail is being sent to you after appropriate authorization or by legal exception. You are obligated to maintain it in a safe, secure and confidential manner. Re-disclosure without patient consent or as permitted by law is prohibited and may subject you to state and/or federal penalties. This information may also be legally privileged, the disclosure of which is governed by law. This information is intended for the use of the person or entity to which it is addressed. If you are not the intended recipient, or the employee or agent responsible for delivering it to the intended recipient, you are hereby notified that any access, disclosure, copying or distribution of this information is strictly prohibited. If you have received this message by error, please notify the sender immediately to arrange for return or proof of destruction of the information contained in this message. ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- To unsubscribe from the MICE-DISCUSS list, click the following link: http://lists.iphouse.net/cgi-bin/wa?SUBED1=MICE-DISCUSS&A=1 <https://gcc02.safelinks.protection.outlook.com/?url=http%3A%2F%2Flists.ipho…> ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- To unsubscribe from the MICE-DISCUSS list, click the following link: http://lists.iphouse.net/cgi-bin/wa?SUBED1=MICE-DISCUSS&A=1 <https://gcc02.safelinks.protection.outlook.com/?url=http%3A%2F%2Flists.ipho…> Disclaimer: If you are not the intended recipient of this message, please immediately notify the sender of the transmission error and then promptly permanently delete this message from your computer system. ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- To unsubscribe from the MICE-DISCUSS list, click the following link: http://lists.iphouse.net/cgi-bin/wa?SUBED1=MICE-DISCUSS&A=1

Nov. 2, 2022

Re: [EXTERNAL] Re: [MICE-DISCUSS] Proposal: MICE Static MAC address Only

by Jeremy Lumby

That was a direct quote from Arista Support. Based on the context that it was used in I would say that means that the forwarding table stopped functioning and the default fallback is to flood everything. They recommended a software update since there were some forwarding table issues fixed in more recent versions, however they could not 100% guarantee the software update would provide complete protection. Arista Support pointed out how destabilizing a loop can be @ 100Gig even if it is only for the 2 seconds that we experienced before port security kicked in (especially with how much traffic an IX is carrying to flow through the loop). When talking with Chris @ the SIX he mentioned that they went to the static ACL method because the port security runs on the control plane, so it will always be slow. A MAC ACL runs on the ASIC so it is about as instantaneous as you are going to get. The port that caused the issue last week had a 1 MAC address limit on it through port security, and not through a MAC ACL. From: MICE Discuss [mailto:MICE-DISCUSS@LISTS.IPHOUSE.NET] On Behalf Of Steve Howard Sent: Wednesday, November 02, 2022 4:59 PM To: MICE-DISCUSS(a)LISTS.IPHOUSE.NET Subject: Re: [MICE-DISCUSS] [EXTERNAL] Re: [MICE-DISCUSS] Proposal: MICE Static MAC address Only What does "crashed the forwarding table" actually mean? Does that mean that the mac address table filled and the switch then flooded to all ports? Was there a mac address limit or a static MAC ACL on the port that caused the problem? On 10/31/22 09:12, Jeremy Lumby wrote: The issue was a member port. The port security took 2 seconds to shutdown the port, however 100G of traffic looped and crashed the forwarding table on the main switch, forcing manual intervention. A static MAC ACL on each port would not have taken time to react. This is what the SIX has been doing on their ports since 2010 (as well as multiple other layers of security). From: MICE Discuss [mailto:MICE-DISCUSS@LISTS.IPHOUSE.NET <MICE-DISCUSS(a)LISTS.IPHOUSE.NET>] On Behalf Of Kittel, Brady Sent: Monday, October 31, 2022 9:07 AM To:MICE-DISCUSS@LISTS.IPHOUSE.NET Subject: Re: [MICE-DISCUSS] [EXTERNAL] Re: [MICE-DISCUSS] Proposal: MICE Static MAC address Only Was the source of the issue a remote switch? " To be clear, this is still only for end ports, not ports facing remoteswitches, of course. The remote switches are responsible for enforcingthe current MAC limit, and would be responsible for changing thosesettings as described here." -Brady --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- From: MICE Discuss<MICE-DISCUSS(a)LISTS.IPHOUSE.NET> <MICE-DISCUSS(a)LISTS.IPHOUSE.NET> on behalf of Jay Hanke<jayhanke(a)SOUTHFRONT.IO> <jayhanke(a)SOUTHFRONT.IO> Sent: Monday, October 31, 2022 9:05:08 AM To:MICE-DISCUSS@LISTS.IPHOUSE.NET<MICE-DISCUSS(a)LISTS.IPHOUSE.NET> <MICE-DISCUSS(a)LISTS.IPHOUSE.NET> Subject: [EXTERNAL] Re: [MICE-DISCUSS] Proposal: MICE Static MAC address Only CAUTION: This email originated from outside of HCMC. DO NOT CLICK links or open attachments unless you recognize the sender and know the content is safe. The error disable takes 1-2 seconds to clamp down and disable the port. This results in a short, but severe, broadcast storm. The churn rate on members changing mac addresses is fairly low. I agree that we should automate the process so it can be done via self-service by the members. On Mon, Oct 31, 2022 at 8:59 AM Steve Howard<showard(a)paulbunyan.net> <showard(a)paulbunyan.net> wrote: > > > Below is a message indicating the current policy as decided by the MICE Board in December 2019 is that the MAC address limit is 1. > > > The subject of Jay's message indicates "Static" MAC, but, the text seems to indicate a limit of 1. I like the 1 address limit, but, am not a fan of Static. Was the current issue caused by somebody not having a proper MAC address limit installed? > > > On 12/13/19 18:00, Richard Laager wrote: > > The board has approved the change in MAC address limit from 5 to 1. > > NOTE: This is orthogonal to the dedicated remote switch question, which > is still pending. Non-dedicated remote switches can, for example, > enforce this per-VLAN. > > We have already confirmed that most participants are using only 1 MAC > address, and some that were using more than 1 have addressed that after > being contacted. As discussed below, this change will be rolled out in a > way to keep everyone working, by grandfathering if necessary. > > On 10/28/19 3:25 PM, Richard Laager wrote: > > We have discussed this a bit in the past, and this came up at the last > UG. I'm looking for feedback from the group before formally proposing > this to the board for a vote. > > I first brought this up to the technical committee, CCing the board. I > have heard no objections. Jeremy is "in favor of it 100%". > > Based on our quick conversation after the UG, I _think_ Anthony is in > favor as well; we both made notes to follow up on this. > > ----- > > I am proposing that MICE change its MAC address limit from 5 MACs per > port to 1 MAC per port. 1 MAC address is enough for normal scenarios and > this would further limit the potential for problems on the fabric. This > restriction is one that SIX and AMS-IX both have, with the latter being > known for their excellent configuration guide for participants: >https://nam02.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.ams-i… > > To be clear, this is still only for end ports, not ports facing remote > switches, of course. The remote switches are responsible for enforcing > the current MAC limit, and would be responsible for changing those > settings as described here. > > If someone is swapping their MICE-facing router, the resulting port flap > on the MICE/remote switch will clear the limit anyway, if they are > directly connected. If they are unable to flap the port (e.g. because > they have someone else's layer 2 gear in the middle), they will have to > either work with that carrier or their switch operator (MICE/remote) to > flap the port. This is a non-zero burden, but I think it's pretty > minimal in practice. Additionally, if someone plans to make an equipment > swap, we would increase the limit in advance, temporarily, upon request. > > For reference, SIX goes further and locks you to a particular MAC > address in an ACL, so you have to contact them to change your MAC. I am > not proposing that. Still, I've been through that a couple of times, and > even that isn't really too big of a deal. So I don't think the change to > a limit of 1 MAC at MICE will be particularly onerous. > > There are a couple of participants who have two IP address sets (one > IPv4 and one IPv6) on the same port. For those ports, the limit > obviously must be at least 2 MACs, but I propose 3 MACs as the limit. If > they're using two IPs, they probably are doing so to get some redundancy > out of it. For this particular use case, needing to flap the port > defeats that redundancy goal, as it breaks the other router. Having a > MAC limit of 3 would allow them to swap a device without needing to flap > the port. We would grandfather these setups until they are looking for a > port-type upgrade; at that point they would need to get to one IP > address set per port (by splitting into two ports or reducing to one IP > address set) or request an exception as outlined below. The exception > process would allow us to better evaluate this use case at that time. > > There are some members who have multiple MACs showing up now, despite > using only one device. For those, I am proposing we set the MAC limit to > however many MACs are currently showing up on their port. That is, they > would be grandfathered at their current situation for now. At the time > of this change, we would encourage them to investigate and fix the > multiple MACs issue at their leisure. In the future, if they are doing a > equipment swap (especially like-for-like), we would again encourage them > to address it, but would otherwise leave their higher limit in place. If > they do a port-type upgrade, we would not bring the grandfathering over. > If they needed, they could ask for an official exception at that time. > > There may be cases where people cannot reasonably fix their routers to > use only 1 MAC, other scenarios I haven't considered, or things that may > come up in the future. For that reason, I think we should allow for the > possibility of exceptions upon request to the board. In practice, I > would expect the board would confer with the technical committee and/or > the technical committee would be bringing these to the board anyway. The > goal is to strike a reasonable balance between protecting the fabric > without preventing networks from connecting. > > > > > On 10/31/22 08:27, Jay Hanke wrote: > > I propose we change the MICE required port security settings to be > hard filtered for a single static mac address per port. > > Over the years, we've had several incidents where floods have occurred > prior to port being error-disabled during a looping event. > > > > ________________________________ > > To unsubscribe from the MICE-DISCUSS list, click the following link: >https://nam02.safelinks.protection.outlook.com/?url=http%3A%2F%2Flists.ipho… -- Jay Hanke, President South Front Networks jayhanke(a)southfront.io Phone 612-204-0000 Confidentiality Notice: Information contained in this e-mail is being sent to you after appropriate authorization or by legal exception. You are obligated to maintain it in a safe, secure and confidential manner. Re-disclosure without patient consent or as permitted by law is prohibited and may subject you to state and/or federal penalties. This information may also be legally privileged, the disclosure of which is governed by law. This information is intended for the use of the person or entity to which it is addressed. If you are not the intended recipient, or the employee or agent responsible for delivering it to the intended recipient, you are hereby notified that any access, disclosure, copying or distribution of this information is strictly prohibited. If you have received this message by error, please notify the sender immediately to arrange for return or proof of destruction of the information contained in this message. --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- To unsubscribe from the MICE-DISCUSS list, click the following link: http://lists.iphouse.net/cgi-bin/wa?SUBED1=MICE-DISCUSS&A=1 --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- To unsubscribe from the MICE-DISCUSS list, click the following link: http://lists.iphouse.net/cgi-bin/wa?SUBED1=MICE-DISCUSS&A=1 ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- To unsubscribe from the MICE-DISCUSS list, click the following link: http://lists.iphouse.net/cgi-bin/wa?SUBED1=MICE-DISCUSS&A=1

Nov. 2, 2022

Re: [EXTERNAL] Re: [MICE-DISCUSS] Proposal: MICE Static MAC address Only

by Steve Howard

Nov. 2, 2022

Re: [EXTERNAL] Re: [MICE-DISCUSS] Proposal: MICE Static MAC address Only

by Tom Krenn

I don't know the config of the switch but out of curiosity, would storm control help mitigate the impact on the forwarding table? We might still have 2-3 seconds of disruption but it may avoid the manual intervention and let us keep the more dynamic port security approach. Tom Krenn Network Architect Enterprise Architecture - Information Technology [Hennepin County logo] From: MICE Discuss <MICE-DISCUSS(a)LISTS.IPHOUSE.NET> On Behalf Of Jeremy Lumby Sent: Monday, October 31, 2022 9:12 AM To: MICE-DISCUSS(a)LISTS.IPHOUSE.NET Subject: Re: [MICE-DISCUSS] [EXTERNAL] Re: [MICE-DISCUSS] Proposal: MICE Static MAC address Only The issue was a member port. The port security took 2 seconds to shutdown the port, however 100G of traffic looped and crashed the forwarding table on the main switch, forcing manual intervention. A static MAC ACL on each port would not have taken time to react. This is what the SIX has been doing on their ports since 2010 (as well as multiple other layers of security). From: MICE Discuss [mailto:MICE-DISCUSS@LISTS.IPHOUSE.NET] On Behalf Of Kittel, Brady Sent: Monday, October 31, 2022 9:07 AM To: MICE-DISCUSS(a)LISTS.IPHOUSE.NET<mailto:MICE-DISCUSS@LISTS.IPHOUSE.NET> Subject: Re: [MICE-DISCUSS] [EXTERNAL] Re: [MICE-DISCUSS] Proposal: MICE Static MAC address Only Was the source of the issue a remote switch? " To be clear, this is still only for end ports, not ports facing remote switches, of course. The remote switches are responsible for enforcing the current MAC limit, and would be responsible for changing those settings as described here." -Brady ________________________________ From: MICE Discuss <MICE-DISCUSS(a)LISTS.IPHOUSE.NET<mailto:MICE-DISCUSS@LISTS.IPHOUSE.NET>> on behalf of Jay Hanke <jayhanke(a)SOUTHFRONT.IO<mailto:jayhanke@SOUTHFRONT.IO>> Sent: Monday, October 31, 2022 9:05:08 AM To: MICE-DISCUSS(a)LISTS.IPHOUSE.NET<mailto:MICE-DISCUSS@LISTS.IPHOUSE.NET> <MICE-DISCUSS(a)LISTS.IPHOUSE.NET<mailto:MICE-DISCUSS@LISTS.IPHOUSE.NET>> Subject: [EXTERNAL] Re: [MICE-DISCUSS] Proposal: MICE Static MAC address Only CAUTION: This email originated from outside of HCMC. DO NOT CLICK links or open attachments unless you recognize the sender and know the content is safe. The error disable takes 1-2 seconds to clamp down and disable the port. This results in a short, but severe, broadcast storm. The churn rate on members changing mac addresses is fairly low. I agree that we should automate the process so it can be done via self-service by the members. On Mon, Oct 31, 2022 at 8:59 AM Steve Howard <showard(a)paulbunyan.net<mailto:showard@paulbunyan.net>> wrote: > > > Below is a message indicating the current policy as decided by the MICE Board in December 2019 is that the MAC address limit is 1. > > > The subject of Jay's message indicates "Static" MAC, but, the text seems to indicate a limit of 1. I like the 1 address limit, but, am not a fan of Static. Was the current issue caused by somebody not having a proper MAC address limit installed? > > > On 12/13/19 18:00, Richard Laager wrote: > > The board has approved the change in MAC address limit from 5 to 1. > > NOTE: This is orthogonal to the dedicated remote switch question, which > is still pending. Non-dedicated remote switches can, for example, > enforce this per-VLAN. > > We have already confirmed that most participants are using only 1 MAC > address, and some that were using more than 1 have addressed that after > being contacted. As discussed below, this change will be rolled out in a > way to keep everyone working, by grandfathering if necessary. > > On 10/28/19 3:25 PM, Richard Laager wrote: > > We have discussed this a bit in the past, and this came up at the last > UG. I'm looking for feedback from the group before formally proposing > this to the board for a vote. > > I first brought this up to the technical committee, CCing the board. I > have heard no objections. Jeremy is "in favor of it 100%". > > Based on our quick conversation after the UG, I _think_ Anthony is in > favor as well; we both made notes to follow up on this. > > ----- > > I am proposing that MICE change its MAC address limit from 5 MACs per > port to 1 MAC per port. 1 MAC address is enough for normal scenarios and > this would further limit the potential for problems on the fabric. This > restriction is one that SIX and AMS-IX both have, with the latter being > known for their excellent configuration guide for participants: > https://nam02.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.ams-i…<https://gcc02.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.ams-i…> > > To be clear, this is still only for end ports, not ports facing remote > switches, of course. The remote switches are responsible for enforcing > the current MAC limit, and would be responsible for changing those > settings as described here. > > If someone is swapping their MICE-facing router, the resulting port flap > on the MICE/remote switch will clear the limit anyway, if they are > directly connected. If they are unable to flap the port (e.g. because > they have someone else's layer 2 gear in the middle), they will have to > either work with that carrier or their switch operator (MICE/remote) to > flap the port. This is a non-zero burden, but I think it's pretty > minimal in practice. Additionally, if someone plans to make an equipment > swap, we would increase the limit in advance, temporarily, upon request. > > For reference, SIX goes further and locks you to a particular MAC > address in an ACL, so you have to contact them to change your MAC. I am > not proposing that. Still, I've been through that a couple of times, and > even that isn't really too big of a deal. So I don't think the change to > a limit of 1 MAC at MICE will be particularly onerous. > > There are a couple of participants who have two IP address sets (one > IPv4 and one IPv6) on the same port. For those ports, the limit > obviously must be at least 2 MACs, but I propose 3 MACs as the limit. If > they're using two IPs, they probably are doing so to get some redundancy > out of it. For this particular use case, needing to flap the port > defeats that redundancy goal, as it breaks the other router. Having a > MAC limit of 3 would allow them to swap a device without needing to flap > the port. We would grandfather these setups until they are looking for a > port-type upgrade; at that point they would need to get to one IP > address set per port (by splitting into two ports or reducing to one IP > address set) or request an exception as outlined below. The exception > process would allow us to better evaluate this use case at that time. > > There are some members who have multiple MACs showing up now, despite > using only one device. For those, I am proposing we set the MAC limit to > however many MACs are currently showing up on their port. That is, they > would be grandfathered at their current situation for now. At the time > of this change, we would encourage them to investigate and fix the > multiple MACs issue at their leisure. In the future, if they are doing a > equipment swap (especially like-for-like), we would again encourage them > to address it, but would otherwise leave their higher limit in place. If > they do a port-type upgrade, we would not bring the grandfathering over. > If they needed, they could ask for an official exception at that time. > > There may be cases where people cannot reasonably fix their routers to > use only 1 MAC, other scenarios I haven't considered, or things that may > come up in the future. For that reason, I think we should allow for the > possibility of exceptions upon request to the board. In practice, I > would expect the board would confer with the technical committee and/or > the technical committee would be bringing these to the board anyway. The > goal is to strike a reasonable balance between protecting the fabric > without preventing networks from connecting. > > > > > On 10/31/22 08:27, Jay Hanke wrote: > > I propose we change the MICE required port security settings to be > hard filtered for a single static mac address per port. > > Over the years, we've had several incidents where floods have occurred > prior to port being error-disabled during a looping event. > > > > ________________________________ > > To unsubscribe from the MICE-DISCUSS list, click the following link: > https://nam02.safelinks.protection.outlook.com/?url=http%3A%2F%2Flists.ipho…<https://gcc02.safelinks.protection.outlook.com/?url=http%3A%2F%2Flists.ipho…> -- Jay Hanke, President South Front Networks jayhanke(a)southfront.io<mailto:jayhanke@southfront.io> Phone 612-204-0000 Confidentiality Notice: Information contained in this e-mail is being sent to you after appropriate authorization or by legal exception. You are obligated to maintain it in a safe, secure and confidential manner. Re-disclosure without patient consent or as permitted by law is prohibited and may subject you to state and/or federal penalties. This information may also be legally privileged, the disclosure of which is governed by law. This information is intended for the use of the person or entity to which it is addressed. If you are not the intended recipient, or the employee or agent responsible for delivering it to the intended recipient, you are hereby notified that any access, disclosure, copying or distribution of this information is strictly prohibited. If you have received this message by error, please notify the sender immediately to arrange for return or proof of destruction of the information contained in this message. ________________________________ To unsubscribe from the MICE-DISCUSS list, click the following link: http://lists.iphouse.net/cgi-bin/wa?SUBED1=MICE-DISCUSS&A=1<https://gcc02.safelinks.protection.outlook.com/?url=http%3A%2F%2Flists.ipho…> ________________________________ To unsubscribe from the MICE-DISCUSS list, click the following link: http://lists.iphouse.net/cgi-bin/wa?SUBED1=MICE-DISCUSS&A=1<https://gcc02.safelinks.protection.outlook.com/?url=http%3A%2F%2Flists.ipho…> Disclaimer: If you are not the intended recipient of this message, please immediately notify the sender of the transmission error and then promptly permanently delete this message from your computer system.

Nov. 2, 2022

Re: Proposal: MICE Static MAC address Only

by Jay Hanke

Yes. The remote switch terms cover this for sharing a single MICE uplink. Also, when a problem arises, we can kill a port without doing a packet capture and only the offending member can be shut off. On Wed, Nov 2, 2022 at 3:23 PM David Farmer <0000000e7948cb21-dmarc-request(a)lists.iphouse.net> wrote: > > And if we statically define the MAC to port mapping do we care? > > On Wed, Nov 2, 2022 at 3:01 PM Jay Hanke <jayhanke(a)southfront.io> wrote: >> >> The hard limit is to keep someone from stacking networks behind a port. >> >> On Wed, Nov 2, 2022 at 2:58 PM David Farmer >> <0000000e7948cb21-dmarc-request(a)lists.iphouse.net> wrote: >> > >> > Maybe we don't need to define a hard limit of 1 or 2, but only that the list needs to be static, as in not auto-detected but a defined list; the point is to be able to quash/filter unknown unicast traffic. >> > >> > On Wed, Nov 2, 2022 at 9:33 AM Jay Hanke <jayhanke(a)southfront.io> wrote: >> >> >> >> What if we raised the maximum number of static mac addresses to 2 (to >> >> allow for migrations and to allow Jeremy to sleep) in the mac acl? >> >> >> >> On Mon, Oct 31, 2022 at 12:48 PM Mike Johnston <mjohnston(a)wiktel.com> wrote: >> >> > >> >> > Well articulated, as always, David. Thank you. >> >> > >> >> > >> >> > I am in favor of the use of static MAC ACL, even if that requires manual >> >> > changes to that ACL, and the additional coordination that may consume. >> >> > A few thoughts, though.... >> >> > >> >> > Maybe 1G links are exempt from this? Since a couple second switching >> >> > loop from a 1G port is not as impactful? ????? Thoughts from others, >> >> > please. >> >> > >> >> > Using a static MAC ACL could make troubleshooting a failure more >> >> > problematic. For example, replacing a line card to "see if that fixes >> >> > the issue" could send a tech down a trail of red hearings. Even if the >> >> > member is fully aware that they need to coordinate the MAC change, this >> >> > sort work is often being done in response to an unexpected outage. The >> >> > added time spend on the coordination could be seen as frustrating. But, >> >> > for some members it's not a big deal, and can use other links until >> >> > their MICE connectivity is restored. >> >> > >> >> > I've heard that some members are using a virtual MAC address, which is >> >> > probably the way to avoid needing to coordinate in the first place. >> >> >> >> >> >> >> >> -- >> >> Jay Hanke, President >> >> South Front Networks >> >> jayhanke(a)southfront.io >> >> Phone 612-204-0000 >> > >> > >> > >> > -- >> > =============================================== >> > David Farmer Email:farmer@umn.edu >> > Networking & Telecommunication Services >> > Office of Information Technology >> > University of Minnesota >> > 2218 University Ave SE Phone: 612-626-0815 >> > Minneapolis, MN 55414-3029 Cell: 612-812-9952 >> > =============================================== >> > >> > ________________________________ >> > >> > To unsubscribe from the MICE-DISCUSS list, click the following link: >> > http://lists.iphouse.net/cgi-bin/wa?SUBED1=MICE-DISCUSS&A=1 >> >> >> >> -- >> Jay Hanke, President >> South Front Networks >> jayhanke(a)southfront.io >> Phone 612-204-0000 > > > > -- > =============================================== > David Farmer Email:farmer@umn.edu > Networking & Telecommunication Services > Office of Information Technology > University of Minnesota > 2218 University Ave SE Phone: 612-626-0815 > Minneapolis, MN 55414-3029 Cell: 612-812-9952 > =============================================== > > ________________________________ > > To unsubscribe from the MICE-DISCUSS list, click the following link: > http://lists.iphouse.net/cgi-bin/wa?SUBED1=MICE-DISCUSS&A=1 -- Jay Hanke, President South Front Networks jayhanke(a)southfront.io Phone 612-204-0000

Nov. 2, 2022

Re: Proposal: MICE Static MAC address Only

by David Farmer

And if we statically define the MAC to port mapping do we care? On Wed, Nov 2, 2022 at 3:01 PM Jay Hanke <jayhanke(a)southfront.io> wrote: > The hard limit is to keep someone from stacking networks behind a port. > > On Wed, Nov 2, 2022 at 2:58 PM David Farmer > <0000000e7948cb21-dmarc-request(a)lists.iphouse.net> wrote: > > > > Maybe we don't need to define a hard limit of 1 or 2, but only that the > list needs to be static, as in not auto-detected but a defined list; the > point is to be able to quash/filter unknown unicast traffic. > > > > On Wed, Nov 2, 2022 at 9:33 AM Jay Hanke <jayhanke(a)southfront.io> wrote: > >> > >> What if we raised the maximum number of static mac addresses to 2 (to > >> allow for migrations and to allow Jeremy to sleep) in the mac acl? > >> > >> On Mon, Oct 31, 2022 at 12:48 PM Mike Johnston <mjohnston(a)wiktel.com> > wrote: > >> > > >> > Well articulated, as always, David. Thank you. > >> > > >> > > >> > I am in favor of the use of static MAC ACL, even if that requires > manual > >> > changes to that ACL, and the additional coordination that may consume. > >> > A few thoughts, though.... > >> > > >> > Maybe 1G links are exempt from this? Since a couple second switching > >> > loop from a 1G port is not as impactful? ????? Thoughts from others, > >> > please. > >> > > >> > Using a static MAC ACL could make troubleshooting a failure more > >> > problematic. For example, replacing a line card to "see if that fixes > >> > the issue" could send a tech down a trail of red hearings. Even if the > >> > member is fully aware that they need to coordinate the MAC change, > this > >> > sort work is often being done in response to an unexpected outage. > The > >> > added time spend on the coordination could be seen as frustrating. > But, > >> > for some members it's not a big deal, and can use other links until > >> > their MICE connectivity is restored. > >> > > >> > I've heard that some members are using a virtual MAC address, which is > >> > probably the way to avoid needing to coordinate in the first place. > >> > >> > >> > >> -- > >> Jay Hanke, President > >> South Front Networks > >> jayhanke(a)southfront.io > >> Phone 612-204-0000 > > > > > > > > -- > > =============================================== > > David Farmer Email:farmer@umn.edu > > Networking & Telecommunication Services > > Office of Information Technology > > University of Minnesota > > 2218 University Ave SE Phone: 612-626-0815 > > Minneapolis, MN 55414-3029 Cell: 612-812-9952 > > =============================================== > > > > ________________________________ > > > > To unsubscribe from the MICE-DISCUSS list, click the following link: > > http://lists.iphouse.net/cgi-bin/wa?SUBED1=MICE-DISCUSS&A=1 > > > > -- > Jay Hanke, President > South Front Networks > jayhanke(a)southfront.io > Phone 612-204-0000 > -- =============================================== David Farmer Email:farmer@umn.edu Networking & Telecommunication Services Office of Information Technology University of Minnesota 2218 University Ave SE Phone: 612-626-0815 Minneapolis, MN 55414-3029 Cell: 612-812-9952 ===============================================

Nov. 2, 2022

Re: Proposal: MICE Static MAC address Only

by Jay Hanke

The hard limit is to keep someone from stacking networks behind a port. On Wed, Nov 2, 2022 at 2:58 PM David Farmer <0000000e7948cb21-dmarc-request(a)lists.iphouse.net> wrote: > > Maybe we don't need to define a hard limit of 1 or 2, but only that the list needs to be static, as in not auto-detected but a defined list; the point is to be able to quash/filter unknown unicast traffic. > > On Wed, Nov 2, 2022 at 9:33 AM Jay Hanke <jayhanke(a)southfront.io> wrote: >> >> What if we raised the maximum number of static mac addresses to 2 (to >> allow for migrations and to allow Jeremy to sleep) in the mac acl? >> >> On Mon, Oct 31, 2022 at 12:48 PM Mike Johnston <mjohnston(a)wiktel.com> wrote: >> > >> > Well articulated, as always, David. Thank you. >> > >> > >> > I am in favor of the use of static MAC ACL, even if that requires manual >> > changes to that ACL, and the additional coordination that may consume. >> > A few thoughts, though.... >> > >> > Maybe 1G links are exempt from this? Since a couple second switching >> > loop from a 1G port is not as impactful? ????? Thoughts from others, >> > please. >> > >> > Using a static MAC ACL could make troubleshooting a failure more >> > problematic. For example, replacing a line card to "see if that fixes >> > the issue" could send a tech down a trail of red hearings. Even if the >> > member is fully aware that they need to coordinate the MAC change, this >> > sort work is often being done in response to an unexpected outage. The >> > added time spend on the coordination could be seen as frustrating. But, >> > for some members it's not a big deal, and can use other links until >> > their MICE connectivity is restored. >> > >> > I've heard that some members are using a virtual MAC address, which is >> > probably the way to avoid needing to coordinate in the first place. >> >> >> >> -- >> Jay Hanke, President >> South Front Networks >> jayhanke(a)southfront.io >> Phone 612-204-0000 > > > > -- > =============================================== > David Farmer Email:farmer@umn.edu > Networking & Telecommunication Services > Office of Information Technology > University of Minnesota > 2218 University Ave SE Phone: 612-626-0815 > Minneapolis, MN 55414-3029 Cell: 612-812-9952 > =============================================== > > ________________________________ > > To unsubscribe from the MICE-DISCUSS list, click the following link: > http://lists.iphouse.net/cgi-bin/wa?SUBED1=MICE-DISCUSS&A=1 -- Jay Hanke, President South Front Networks jayhanke(a)southfront.io Phone 612-204-0000

Nov. 2, 2022

Re: Proposal: MICE Static MAC address Only

by David Farmer

Maybe we don't need to define a hard limit of 1 or 2, but only that the list needs to be static, as in not auto-detected but a defined list; the point is to be able to quash/filter unknown unicast traffic. On Wed, Nov 2, 2022 at 9:33 AM Jay Hanke <jayhanke(a)southfront.io> wrote: > What if we raised the maximum number of static mac addresses to 2 (to > allow for migrations and to allow Jeremy to sleep) in the mac acl? > > On Mon, Oct 31, 2022 at 12:48 PM Mike Johnston <mjohnston(a)wiktel.com> > wrote: > > > > Well articulated, as always, David. Thank you. > > > > > > I am in favor of the use of static MAC ACL, even if that requires manual > > changes to that ACL, and the additional coordination that may consume. > > A few thoughts, though.... > > > > Maybe 1G links are exempt from this? Since a couple second switching > > loop from a 1G port is not as impactful? ????? Thoughts from others, > > please. > > > > Using a static MAC ACL could make troubleshooting a failure more > > problematic. For example, replacing a line card to "see if that fixes > > the issue" could send a tech down a trail of red hearings. Even if the > > member is fully aware that they need to coordinate the MAC change, this > > sort work is often being done in response to an unexpected outage. The > > added time spend on the coordination could be seen as frustrating. But, > > for some members it's not a big deal, and can use other links until > > their MICE connectivity is restored. > > > > I've heard that some members are using a virtual MAC address, which is > > probably the way to avoid needing to coordinate in the first place. > > > > -- > Jay Hanke, President > South Front Networks > jayhanke(a)southfront.io > Phone 612-204-0000 > -- =============================================== David Farmer Email:farmer@umn.edu Networking & Telecommunication Services Office of Information Technology University of Minnesota 2218 University Ave SE Phone: 612-626-0815 Minneapolis, MN 55414-3029 Cell: 612-812-9952 ===============================================

Nov. 2, 2022

Re: Proposal: MICE Static MAC address Only

by Jay Hanke

What if we raised the maximum number of static mac addresses to 2 (to allow for migrations and to allow Jeremy to sleep) in the mac acl? On Mon, Oct 31, 2022 at 12:48 PM Mike Johnston <mjohnston(a)wiktel.com> wrote: > > Well articulated, as always, David. Thank you. > > > I am in favor of the use of static MAC ACL, even if that requires manual > changes to that ACL, and the additional coordination that may consume. > A few thoughts, though.... > > Maybe 1G links are exempt from this? Since a couple second switching > loop from a 1G port is not as impactful? ????? Thoughts from others, > please. > > Using a static MAC ACL could make troubleshooting a failure more > problematic. For example, replacing a line card to "see if that fixes > the issue" could send a tech down a trail of red hearings. Even if the > member is fully aware that they need to coordinate the MAC change, this > sort work is often being done in response to an unexpected outage. The > added time spend on the coordination could be seen as frustrating. But, > for some members it's not a big deal, and can use other links until > their MICE connectivity is restored. > > I've heard that some members are using a virtual MAC address, which is > probably the way to avoid needing to coordinate in the first place. -- Jay Hanke, President South Front Networks jayhanke(a)southfront.io Phone 612-204-0000

Nov. 2, 2022