Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

bgpd: Withdraw routes without waiting for the coalescing timer to expire #17667

Open
wants to merge 1 commit into
base: master
Choose a base branch
from

Conversation

ton31337
Copy link
Member

No description provided.

@frrbot frrbot bot added the bgp label Dec 18, 2024
@ton31337 ton31337 force-pushed the fix/withdraw_routes_regarless_of_coalescing_timer_to_expire_path_info_unusable branch from 9d6c53b to d4c03e9 Compare December 18, 2024 12:08
@ton31337 ton31337 marked this pull request as draft December 18, 2024 12:09
TL;DR; BGP keeps advertising prefixes which were already removed via `network`
command.

This was happening randomly, but with this patch, no issues happened.

Before:

```
frr# sh ip bgp neighbors 10.0.5.1 advertised-routes
BGP table version is 586, local router ID is 44.44.33.43, vrf id 0
Default local pref 100, local AS 2
Status codes: s suppressed, d damped, h history, * valid, > best, = multipath,
i internal, r RIB-failure, S Stale, R Removed
Nexthop codes: @NNN nexthop's vrf id, < announce-nh-self
Origin codes: i - IGP, e - EGP, ? - incomplete
RPKI validation codes: V valid, I invalid, N Not found

Network Next Hop Metric LocPrf Weight Path
*> 15.15.15.0/24 0.0.0.0 0 32768 2 i ============> stale entry
*> 15.15.16.0/24 0.0.0.0 0 32768 2 i
*> 15.15.17.0/24 0.0.0.0 0 32768 2 i

frr# sh ip bgp 15.15.15.0/24
% Network not in table
```

Logs:

```
root@b03d1542-0215-5ecf-013d-af2a7150a4f5:~# cat /log/syslog/frr.log | grep 15.15.15.0
2024/12/08 07:56:58 BGP: [K423X-ETGCQ] group_announce_route_walkcb: afi=IPv4, safi=unicast, p=15.15.15.0/24
2024/12/08 07:56:58 BGP: [T5JFA-13199] subgroup_process_announce_selected: p=15.15.15.0/24, selected=0xde4060
2024/12/08 07:56:58 BGP: [K423X-ETGCQ] group_announce_route_walkcb: afi=IPv4, safi=unicast, p=15.15.15.0/24
2024/12/08 07:56:58 BGP: [T5JFA-13199] subgroup_process_announce_selected: p=15.15.15.0/24, selected=0xde4060
2024/12/08 07:56:58 BGP: [HVRWP-5R9NQ] u78:s77 send UPDATE 15.15.15.0/24 IPv4 unicast
```

Or imagine the situation where withdrawals are postponed for 20-30s., blackholing
happens.

Signed-off-by: Donatas Abraitis <[email protected]>
@ton31337 ton31337 force-pushed the fix/withdraw_routes_regarless_of_coalescing_timer_to_expire_path_info_unusable branch from d4c03e9 to 92c92ae Compare December 18, 2024 12:26
@ton31337 ton31337 marked this pull request as ready for review December 18, 2024 13:42
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Projects
None yet
Development

Successfully merging this pull request may close these issues.

1 participant