sr - spring - what's the deal with 2 names

aaron1 at aaron1 at
Thu Sep 10 19:09:44 UTC 2020

Thanks for the heads up Mark... I see docs showing SRv6 not supported until XR 6.6, I put XR7 in my lab to start testing it...

I have what seems to be a good test for vpnv4 mpls l3vpn over SRv6 IS-IS in core

This is my first go at this so still learning.  Srv6 has a strange locator thing with it.  Here's a PE with a CEF entry showing the remote l3vpn subnet.  Interesting about the SRv6 T.Encaps.Red thing

RP/0/RP0/CPU0:r1#sh cef vrf one
Thu Sep 10 18:57:04.082 UTC, version 3, SRv6 Transit, internal 0x5000001 0x0 (ptr 0xe208f5c) [1], 0x0 (0xe3d45a8), 0x0 (0xf1ce1a8)
 Updated Sep 10 18:47:58.416
 Prefix Len 30, traffic index 0, precedence n/a, priority 3
   via fc00:0:0:4::/128, 3 dependencies, recursive [flags 0x6000]
    path-idx 0 NHID 0x0 [0xd905574 0x0]
    next hop VRF - 'default', table - 0xe0800000
    next hop fc00:0:0:4::/128 via fc00:0:0:4::/64
    SRv6 T.Encaps.Red SID-list {fc00:0:0:4:41::}

I only used link local default fe80 on the transit core interfaces...

Only added a rfc4193 fc00 address to each loopback to get bgp session to come up.  Works

Ce to ce can ping 

Interesting looking trace from pe lo0 to pe lo0

RP/0/RP0/CPU0:r4#traceroute fc00:0:1:1::1 source fc00:0:4:4::1
Thu Sep 10 19:02:55.211 UTC

Type escape sequence to abort.
Tracing the route to fc00:0:1:1::1

 1  ::ffff: 16 msec 7 msec 8 msec
 2  ::ffff: 6 msec 5 msec 6 msec
 3  fc00:0:1:1::1 92 msec 86 msec 80 msec


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