There was a break for ISIS segment routing that happened accidentally during a refactor. @c-po spotted the issue and showed me where it was broken. I fixed the break and I am implementing a smoketest to catch if it breaks in the future.
Description
Description
Details
Details
- Difficulty level
- Normal (likely a few hours)
- Version
- 1.4
- Why the issue appeared?
- Other
- Is it a breaking change?
- Perfectly compatible
- Issue type
- Bug (incorrect behavior)
Event Timeline
Comment Actions
Good news. It seems the patch worked properly. Here we show MPLS labels generated via segment routing for the prefix command:
Configuration added is, where X is the loopback IP of the local router:
set protocols isis segment-routing prefix 192.168.0.x/32 index value 'x'
vyos@BB1-VYOS:~$ show mpls table Inbound Label Type Nexthop Outbound Label ------------------------------------------------------------------ 1002 SR (IS-IS) 192.168.255.9 implicit-null 1003 SR (IS-IS) 192.168.255.9 1003 <--- Here is the new generated prefix label 1004 SR (IS-IS) 192.168.255.9 1004 <--- Here is the new generated prefix label 1005 SR (IS-IS) 192.168.255.1 implicit-null 1006 SR (IS-IS) 192.168.255.9 1006 <--- Here is the new generated prefix label 1006 SR (IS-IS) 192.168.255.1 1006 <--- Here is the new generated prefix label 1007 SR (IS-IS) 192.168.255.9 1007 <--- Here is the new generated prefix label 1007 SR (IS-IS) 192.168.255.1 1007 <--- Here is the new generated prefix label 1008 SR (IS-IS) 192.168.255.9 1008 <--- Here is the new generated prefix label 1008 SR (IS-IS) 192.168.255.1 1008 <--- Here is the new generated prefix label 15000 SR (IS-IS) 192.168.255.1 implicit-null 15001 SR (IS-IS) fe80::e06:cfff:fe17:1 implicit-null 15002 SR (IS-IS) 192.168.255.9 implicit-null 15003 SR (IS-IS) fe80::e81:7aff:fe90:3 implicit-null
Here's the routing table showing the same:
vyos@BB1-VYOS:~$ show ip route 192.168.0.0/24 longer-prefixes
Codes: K - kernel route, C - connected, S - static, R - RIP,
O - OSPF, I - IS-IS, B - BGP, E - EIGRP, N - NHRP,
T - Table, v - VNC, V - VNC-Direct, A - Babel, F - PBR,
f - OpenFabric,
> - selected route, * - FIB route, q - queued, r - rejected, b - backup
t - trapped, o - offload failure
C>* 192.168.0.1/32 is directly connected, lo, 00:10:58
I>* 192.168.0.2/32 [115/110] via 192.168.255.9, eth2, label implicit-null, weight 1, 00:00:41
I>* 192.168.0.3/32 [115/210] via 192.168.255.9, eth2, label 1003, weight 1, 00:00:37
I>* 192.168.0.4/32 [115/310] via 192.168.255.9, eth2, label 1004, weight 1, 00:00:33
I>* 192.168.0.5/32 [115/110] via 192.168.255.1, eth1, label implicit-null, weight 1, 00:00:27
I>* 192.168.0.6/32 [115/210] via 192.168.255.1, eth1, label 1006, weight 1, 00:00:21
* via 192.168.255.9, eth2, label 1006, weight 1, 00:00:21
I>* 192.168.0.7/32 [115/310] via 192.168.255.1, eth1, label 1007, weight 1, 00:00:16
* via 192.168.255.9, eth2, label 1007, weight 1, 00:00:16
I>* 192.168.0.8/32 [115/410] via 192.168.255.1, eth1, label 1008, weight 1, 00:00:10
* via 192.168.255.9, eth2, label 1008, weight 1, 00:00:10Comment Actions
Doing further testing, it seems adding the explicit-null broke the configuration:
set protocols isis segment-routing prefix 192.168.0.1/32 index explicit-null
set protocols isis segment-routing prefix 192.168.0.1/32 index value '1'
vyos@BB1-VYOS:~$ show mpls table
Inbound Label Type Nexthop Outbound Label
------------------------------------------------------------------
15000 SR (IS-IS) 192.168.255.1 implicit-null
15001 SR (IS-IS) fe80::e06:cfff:fe17:1 implicit-null
15002 SR (IS-IS) 192.168.255.9 implicit-null
15003 SR (IS-IS) fe80::e81:7aff:fe90:3 implicit-null
vyos@BB1-VYOS:~$ show ip route 192.168.0.0/24 longer-prefixes
Codes: K - kernel route, C - connected, S - static, R - RIP,
O - OSPF, I - IS-IS, B - BGP, E - EIGRP, N - NHRP,
T - Table, v - VNC, V - VNC-Direct, A - Babel, F - PBR,
f - OpenFabric,
> - selected route, * - FIB route, q - queued, r - rejected, b - backup
t - trapped, o - offload failure
C>* 192.168.0.1/32 is directly connected, lo, 00:21:48
I>* 192.168.0.2/32 [115/110] via 192.168.255.9, eth2, weight 1, 00:08:02
I>* 192.168.0.3/32 [115/210] via 192.168.255.9, eth2, weight 1, 00:07:59
I>* 192.168.0.4/32 [115/310] via 192.168.255.9, eth2, weight 1, 00:07:56
I>* 192.168.0.5/32 [115/110] via 192.168.255.1, eth1, weight 1, 00:07:51
I>* 192.168.0.6/32 [115/210] via 192.168.255.1, eth1, weight 1, 00:07:47
* via 192.168.255.9, eth2, weight 1, 00:07:47
I>* 192.168.0.7/32 [115/310] via 192.168.255.1, eth1, weight 1, 00:07:44
* via 192.168.255.9, eth2, weight 1, 00:07:44
I>* 192.168.0.8/32 [115/410] via 192.168.255.1, eth1, weight 1, 00:07:41
* via 192.168.255.9, eth2, weight 1, 00:07:41It seems it removed "prefix" altogether:
router isis VyOS is-type level-2-only net 49.0001.1921.6800.0001.00 segment-routing on segment-routing global-block 1000 1999 segment-routing node-msd 3 exit
Comment Actions
Made a fix and now we have:
vyos@BB1-VYOS:~$ show configuration commands | match isis | grep prefix
set protocols isis segment-routing prefix 192.168.0.1/32 index value '1'
router isis VyOS is-type level-2-only net 49.0001.1921.6800.0001.00 segment-routing on segment-routing global-block 1000 1999 segment-routing node-msd 3 segment-routing prefix 192.168.0.1/32 index 1 <--- works exit
Added the configuration to this:
vyos@BB1-VYOS:~$ show configuration commands | match isis | grep prefix
set protocols isis segment-routing prefix 192.168.0.1/32 index explicit-null
set protocols isis segment-routing prefix 192.168.0.1/32 index value '1'
router isis VyOS is-type level-2-only net 49.0001.1921.6800.0001.00 segment-routing on segment-routing global-block 1000 1999 segment-routing node-msd 3 segment-routing prefix 192.168.0.1/32 index 1 explicit-null <--- works again exit
Added the configuration to this:
vyos@BB1-VYOS:~$ show configuration commands | match isis | grep prefix
set protocols isis segment-routing prefix 192.168.0.1/32 index no-php-flag
set protocols isis segment-routing prefix 192.168.0.1/32 index value '1'
router isis VyOS is-type level-2-only net 49.0001.1921.6800.0001.00 segment-routing on segment-routing global-block 1000 1999 segment-routing node-msd 3 segment-routing prefix 192.168.0.1/32 index 1 no-php-flag <--- works again exit
I added all of them:
vyos@BB1-VYOS:~$ show configuration commands | match isis | grep prefix
set protocols isis segment-routing prefix 192.168.0.1/32 index explicit-null
set protocols isis segment-routing prefix 192.168.0.1/32 index no-php-flag
set protocols isis segment-routing prefix 192.168.0.1/32 index value '1'
This is what I get, and this makes sense because of the way the jinja2 template is coded:
router isis VyOS is-type level-2-only net 49.0001.1921.6800.0001.00 segment-routing on segment-routing global-block 1000 1999 segment-routing node-msd 3 segment-routing prefix 192.168.0.1/32 index 1 no-php-flag exit
Comment Actions
It seems that we have two constraints here.
The first constraint is, if adding the "explicit-null" or the "no-php-flag" options and one wants to switch between them one *must* delete. It seems deleting one and adding the other in one commit doesn't work and doesn't seem to change things. I am unsure how to fix this one.
The second constraint is, we can only have "explicit-null" or "no-php-flag" at one time. Not both at the same time. This makes sense as to my understanding those two options are mutually exclusive. This means I'll have to make a change in the change in the protocols handler to error out if both are configured at the same time.
Comment Actions
It seems we have working ISIS segment routing:
vyos@vyos:~$ show ip route
Codes: K - kernel route, C - connected, S - static, R - RIP,
O - OSPF, I - IS-IS, B - BGP, E - EIGRP, N - NHRP,
T - Table, v - VNC, V - VNC-Direct, A - Babel, F - PBR,
f - OpenFabric,
> - selected route, * - FIB route, q - queued, r - rejected, b - backup
t - trapped, o - offload failure
I 192.168.0.0/31 [115/20] via 192.168.0.1, eth1 inactive, weight 1, 00:03:00
C>* 192.168.0.0/31 is directly connected, eth1, 00:08:46
I>* 192.168.0.2/31 [115/20] via 192.168.0.9, eth2, weight 1, 00:03:00
I>* 192.168.0.4/31 [115/30] via 192.168.0.9, eth2, weight 1, 00:02:59
I>* 192.168.0.6/31 [115/40] via 192.168.0.9, eth2, weight 1, 00:02:58
I 192.168.0.8/31 [115/20] via 192.168.0.9, eth2 inactive, weight 1, 00:03:00
C>* 192.168.0.8/31 is directly connected, eth2, 00:08:44
I>* 192.168.0.10/31 [115/20] via 192.168.0.1, eth1, weight 1, 00:03:00
I>* 192.168.0.12/31 [115/20] via 192.168.0.9, eth2, weight 1, 00:03:00
I>* 192.168.0.14/31 [115/30] via 192.168.0.1, eth1, weight 1, 00:02:56
* via 192.168.0.9, eth2, weight 1, 00:02:56
I>* 192.168.0.16/31 [115/30] via 192.168.0.9, eth2, weight 1, 00:02:59
I>* 192.168.0.18/31 [115/40] via 192.168.0.1, eth1, weight 1, 00:02:56
* via 192.168.0.9, eth2, weight 1, 00:02:56
C>* 192.168.255.1/32 is directly connected, lo, 00:08:47
eight 1, 00:01:02
I>* 192.168.255.3/32 [115/30] via 192.168.0.9, eth2, label 53, weight 1, 00:00:56
I>* 192.168.255.4/32 [115/40] via 192.168.0.9, eth2, label 54, weight 1, 00:00:52
I>* 192.168.255.5/32 [115/20] via 192.168.0.1, eth1, label IPv4 Explicit Null, weight 1, 00:00:47
I>* 192.168.255.6/32 [115/30] via 192.168.0.1, eth1, label 56, weight 1, 00:00:42
* via 192.168.0.9, eth2, label 56, weight 1, 00:00:42
I>* 192.168.255.7/32 [115/40] via 192.168.0.1, eth1, label 57, weight 1, 00:00:37
* via 192.168.0.9, eth2, label 57, weight 1, 00:00:37
I>* 192.168.255.8/32 [115/50] via 192.168.0.1, eth1, label 58, weight 1, 00:00:33
* via 192.168.0.9, eth2, label 58, weight 1, 00:00:33
vyos@vyos:~$vyos@vyos:~$ show mpls table Inbound Label Type Nexthop Outbound Label ---------------------------------------------------------------------- 52 SR (IS-IS) 192.168.0.9 IPv4 Explicit Null 53 SR (IS-IS) 192.168.0.9 53 54 SR (IS-IS) 192.168.0.9 54 55 SR (IS-IS) 192.168.0.1 IPv4 Explicit Null 56 SR (IS-IS) 192.168.0.9 56 56 SR (IS-IS) 192.168.0.1 56 57 SR (IS-IS) 192.168.0.9 57 57 SR (IS-IS) 192.168.0.1 57 58 SR (IS-IS) 192.168.0.9 58 58 SR (IS-IS) 192.168.0.1 58 15000 SR (IS-IS) 192.168.0.9 implicit-null 15001 SR (IS-IS) fe80::e81:7aff:fe90:3 implicit-null 15002 SR (IS-IS) 192.168.0.1 implicit-null 15003 SR (IS-IS) fe80::e06:cfff:fe17:1 implicit-null