Re: [j-nsp] proxy-arp on EVPN irb

Roger Wiklund via juniper-nsp <[email protected]>
Newsgroups gmane.network.nsp.juniper
Message-ID <CAC+aSK03CrrHdpFDXUnprgP3Gv_dK6oWtyUCGBVbvjEPg20jww@mail.gmail.com>
Hi

It seems that proxy arp is disabled by default:
proxy-arp | Junos OS | Juniper Networks
<https://www.juniper.net/documentation/us/en/software/junos/multicast-l2/topics/ref/statement/proxy-arp-edit-interfaces.html>

Regarding proxy-arp for EVPN (arp suppression) it only works for the same
subnet, not between subnets.

So that seems to match what you're seeing that you must enable proxy-arp on
the IRB in order to reach the other subnets.

Regards
Roger


On Wed, Dec 6, 2023 at 5:04 PM Aaron1 via juniper-nsp <
[email protected]> wrote:

> As I recall, proxy-arp behavior is proven by looking in the local host arp
> cache and finding entries for foreign ip’s mapped to the default gateway’s
> mac address.  If that is still occurring, then it would seem that proxy arp
> functionality is still working and you can move on to tshooting something
> beyond that… like what is the upstream def gw/evpn pe doing with those
> packets
>
> Aaron
>
> > On Dec 6, 2023, at 6:16 AM, Jackson, William via juniper-nsp <
> [email protected]> wrote:
> >
> > Hi
> >
> > Maybe somebody knows the answer to this one:
> >
> > We migrated some customers to an EVPN domain away from a legacy node
> that used proxy-arp on its L3 interface.
> >
> > The downstream clients have some funky routing and they are relying on
> proxy-arp to resolve an offnet address (don't ask me why for our sanities
> sake)!
> >
> > We have a implemented EVPN bridge domain with the following config on MX
> PE nodes running 21.1 code.
> >
> > instance-type virtual-switch;
> > protocols {
> >    evpn {
> >        encapsulation mpls;
> >        default-gateway do-not-advertise;
> >        extended-vlan-list [ 250  ];
> >    }
> > }
> > bridge-domains {
> >    250 {
> >        domain-type bridge;
> >        vlan-id 250;
> >        interface ae68.250;
> >        routing-interface irb.25068;
> >    }
> > }
> >
> > interfaces irb.25068 {
> >  proxy-arp;
> >  family inet {
> >      address 172.23.248.1/22;
> >  }
> >  mac 00:aa:dd:00:00:68;
> > }
> >
> > This irb is in a L3VPN instance.
> >
> > Now the documentation states that proxy-arp and arp-suppression is on by
> default yet these clients cant reach the offnet host with or without the
> "proxy-arp" command on the irb.
> >
> > Any ideas?
> >
> > thanks
> > _______________________________________________
> > juniper-nsp mailing list [email protected]
> > https://puck.nether.net/mailman/listinfo/juniper-nsp
>
> _______________________________________________
> juniper-nsp mailing list [email protected]
> https://puck.nether.net/mailman/listinfo/juniper-nsp
>
_______________________________________________
juniper-nsp mailing list [email protected]
https://puck.nether.net/mailman/listinfo/juniper-nsp
lmpx.com only provides a reader for public news (NNTP) servers. It is not affiliated with the servers or forums shown here and is not responsible for the content of articles, which is written by their respective authors.