Dynamic Routing Protocols with IPv6: Configuration, Verification, and Troubleshooting - AMA

[ciscomoderator]

 

Ask Me Anything Forum

In this event we will answer all your questions related to dynamic routing protocols with IPv6 configuration, verification, troubleshooting, and general best current practices. All questions regarding design, in-depth mechanics, and features of the Routing Information Protocol for IPv6, OSPFv3, ISIS, EIGRPv6, and BGP are welcome.

To participate in this event, please use the  button below to ask your questions

Ask questions from Wednesday, April 14 to Tuesday, April 27, 2021

Featured Experts

Gary Bolivar is a Senior Technical Consulting Engineer in the Cisco HTTS (High Touch Technical Support) for Routing and Switching. He specializes in solving advanced routing protocol problems for corporate networks, Service providers , and data centers for customers primarily in North America. He has worked with multiple Cisco platforms and routing protocols for the last seven years. He currently holds dual CCIE, Routing & Switching and Service Provider among others, and a degree in computer science. Gary is also passionate about network automation and scripting.

Harold Ritter is a Senior Technical Leader in the Cisco Advanced Services Group. He has many years of experience as a network architect and works closely with business segment customers and service providers. Among his duties, he is responsible for deploying technologies such as MPLS, IPv6, multicast, and routing protocols in general. He has dual CCIE (Routing & Switching and Service Provider) certifications and regularly conducts presentations on various IPv6 topics, primarily at Cisco Live events.

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[whitlelisa]

Hi guys,

Thanks for the opportunity to reach you!

What is the difference between OSPFv2 and OSPFv3?

Thanks,

Lisa

[Harold Ritter]

Hi,

OSPFv2 is the version that is used to provide connectivity to IPv4 prefixes.

OSPFv3 is commonly used to provide connectivity to IPv6 prefixes, but unlike OSPFv2, it could be used to handle both IPv4 and IPv6.

So a network engineering team could decide to use OSPFv2 for IPv4 and OSPFv3 for IPv6 or OSPFv3 for both.

Obviously if you are already using OSPFv2 for IPv4, it would be easier to just add OSPFv3 to your network, if you are thinking of adding IPv6 to your network. In this scenario, using OSPFv3 for both would mean migrating from OSPFv2 to OSPFv3, which could have impact in your production network.

Regards,

[mohAmed khAdr]

V3 is ipv6 but can be used for ipv4 as well.

big diff is: v3 uses type9:  0x2009 Intra-Area Prefix LSA, which is essential if you going to create stub areas.

HTH

mohamed

[AlainDC010]

How does IS-IS works with IPv6?

Thank you, ADC

[Harold Ritter]

Hi Alain,

ISIS is by definition multi protocol aware and is relatively easy to extend in order to support new protocols. It was among the first routing protocols to support IPv6. It can cope with IPv6 and IPv4 without requiring an additional routing protocol. If you decide to use ISIS for both IPv4 and IPv6, you also need to decide if these two protocols will share the same topology (single topology) or each have their own view of the network (multi topology). The later is normally preferred.

Regards,

[ciscomoderator]

Hi Gary and Harold,
Thanks for your time and effort, we really appreciate it!
We would like to share with you some of the questions that remain unanswered in the community, to help other members.

Packet tracer ipv6 dhcp relay on Cisco ISR4331 from keesepema

I'm working on a Packet Tracer lab (8.5.1).

The lab informs that one needs a Cisco 4221 router.

However, this router is not part of my packet tracer inventory. I'm working on Linux and MacOs. I expect that must be the cause.

I have to implement ipv6 dhcp relay now on a ISR4331 router.

As sofar all went well, however it is not possible to configure a dhcp relay on an ISR4331 interface.

The command

"

Router(config-if)# ipv6 dhcp relay destination <ipv6> <interface>

"

yields:

% Invalid input detected at '^' marker.

My question: what can I do to obtain the 4221 router or it's operating-system image?

[Harold Ritter]

Hi,

I am not a Cisco Packet Tracer expert, but I know that it is generally behind in terms of functionality. I could not find an ISR4221 either and all other routers do not support the ipv6 dhcp relay functionality. I doubt that this functionality is indeed implemented. Could you please send me the link to the lab you are referring to?

Regards,

[ciscomoderator]

Do Cisco FirePower Threat Defense Firewalls support IPv6 Multicast Routing? from lrnaust

Hello,

My program is working on transitioning to IPv6 and in our current IPv4 network architecture we're using the ASA 5525/5555-x series firewalls to do multicast routing. I recently read the ASA 5500-x series firewalls do not support IPv6 multicast routing. I was wondering if the NGFW Firepower Threat Defense Firewalls support IPv6 multicast routing?  Because I'm not seeing much information in cisco documentation about this topic. Thank you.

[ciscomoderator]

Hello,

My program is working on transitioning to IPv6 and in our current IPv4 network architecture we're using the ASA 5525/5555-x series firewalls to do multicast routing. I recently read the ASA 5500-x series firewalls do not support IPv6 multicast routing. I was wondering if the NGFW Firepower Threat Defense Firewalls support IPv6 multicast routing?  Because I'm not seeing much information in cisco documentation about this topic. Thank you.

[gbolivar]

Hi,

IPv6 Multicast routing is not supported yet on NGFW FTD. I will recommend you to check the configuration guide for future releases.

Multicast Routing for Firepower Threat Defense: 

https://www.cisco.com/c/en/us/td/docs/security/firepower/670/configuration/guide/fpmc-config-guide-v67/multicast_routing_for_firepower_threat_defense.html 

Multicast Routing for ASA:

https://www.cisco.com/c/en/us/td/docs/security/asa/asa910/configuration/general/asa-910-general-config/route-multicast.html

Regards,

Gary,

Sr Technical Consulting Engineer

[ciscomoderator]

Does configuring ipv6 address on already configured and functional ipv4 interface interrupt service ? from usmansa1

Hi,

I have been given task to configure the IPv6 service on the interface which has already ipv4 address configured and BGP peer established and working. My question is that is configuring ipv6 address on same interface with already working ipv4 and bgp will interrupt any service or not. Subsequently I have to configure the bgp peering as well for IPv6. Does this has any impact on ipv4 service which is already working through the same interface ?

My device is Catalyst 4500

[ciscomoderator]

Hi,

I have been given task to configure the IPv6 service on the interface which has already ipv4 address configured and BGP peer established and working. My question is that is configuring ipv6 address on same interface with already working ipv4 and bgp will interrupt any service or not. Subsequently I have to configure the bgp peering as well for IPv6. Does this has any impact on ipv4 service which is already working through the same interface ?

My device is Catalyst 4500

[Harold Ritter]

Hi,

In principle, enabling IPv6 should not impact your IPv4 traffic, assuming the equipment has sufficient resources. You should always check the device health before you enabled any new feature of functionality on a given device. If the equipment is nearing its capacity in terms of memory and cpu, enabling a new feature might impact the existing traffic.

Regards,

[Adams A.]

Hey Harold, how are you ?
My question is not really technical.... We've been talking about IPv6 adoption for years now... The main reason brought to the table was that we would soon run out of IPv4 public IP addresses... But clearly, years later, I  have not run into a single client using IPv6 or even considering it... Some even have unused /16 IPv4 blocks. 

So I'ld like to have your overall opinion on the IPv6 adoption theory vs reality both in the enterprise and service provider worlds.

Thanks!

Adams

[Harold Ritter]

Hi Adams,

I am doing well. Hope you are too. The situation with the IPv4 address shortage is really critical. All of the RIR (ARIN, RIPE, LACNIC, APNIC, AfriNIC) have reached the end of their stock and are running on reserve. They all have very restricting policies to grant what is left  to who ever might need new IPv4 addresses.

The good news is that IPv6 deployment is  going well worldwide, at least for the service providers and the content providers. A very large portion of the worldwide Internet traffic is currently taking place over IPv6. Some interesting statistics are available from different source on this topic.

Network operator measurements, 10th March 2021

https://www.worldipv6launch.org/measurements/

Akamai IPv6 Adoption Visualization

https://www.akamai.com/us/en/resources/our-thinking/state-of-the-internet-report/state-of-the-internet-ipv6-adoption-visualization.jsp

Google Global IPv6 Adoption (35%)

https://www.google.com/intl/en/ipv6/statistics.html#tab=ipv6-adoption

That being said, I think there is a lot of work ahead of us, especially in the enterprise space. 

What I normally recommend to our enterprise customers is to get ready by starting with making their Internet presence available over IPv6. This is a very important part and makes sure that they will provide their content over the legacy Internet and the new Internet for their customer.

I hope I addressed you question. Please let me know if you have any other questions or concerns.

Regards,

[Nono82]

Hi everyone

Can you please help me to clarify what is the difference between 6PE and 6VPE?

Thank you in advance!

Nono