Community discussions

MikroTik App
 
Gunni
just joined
Topic Author
Posts: 4
Joined: Fri Feb 11, 2022 5:25 am

[BGP] add-path-out seems to be ignored

Wed Dec 14, 2022 4:50 am

Hey,

So I am trying to setup a BGP session to forward _all_ routes to a service.

So I set the BGP session to have `add-path-out=all`.

According to my understanding it should send all the prefixes I have, not just the best paths.

I have 3 upstreams with 162.411+165.465+158.785 routes, totalling 486.661 prefixes.

The service receiving my routes only reports the max number 165.465, not 486.661 which I am expecting.

Am I understanding how this should work wrong?

EDIT: Figured out how to do this

1. REMOVE the "Remote AS" from the BGP session
2. Set the "Local Role" to "ibgp rr"

That's it, I think! Only seeing 302k routes but still!
 
User avatar
rextended
Forum Guru
Forum Guru
Posts: 11982
Joined: Tue Feb 25, 2014 12:49 pm
Location: Italy
Contact:

Re: [BGP] add-path-out seems to be ignored

Wed Dec 14, 2022 12:17 pm

Missing details like RouterOS version.
 
Gunni
just joined
Topic Author
Posts: 4
Joined: Fri Feb 11, 2022 5:25 am

Re: [BGP] add-path-out seems to be ignored

Sat Dec 17, 2022 5:36 pm

Apologies, I am running on v7.6.
 
Gunni
just joined
Topic Author
Posts: 4
Joined: Fri Feb 11, 2022 5:25 am

Re: [BGP] add-path-out seems to be ignored

Sun Dec 18, 2022 7:21 pm

Hey,

So I have been looking further into this, the edit above is inaccurate, the extra routes were not the duplicate routes I was trying to advertise, but instead my CYMRU blackholes were being sent to the service. Thankfully the information is not being used for routing packets, just informational.

After filtering out CYMRU routes, I am back to where I started. add-path-out seems to do nothing.

In fact, it does not even get added as a capability.

Screenshot 2022-12-18 171555.png

 0   name="bgp_xxxxxxxxxxx" 
     remote.address=2a0c:xxxx:xxxx::xxxx/128 
     local.address=2001:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx .role=ibgp-rr 
     routing-table=main router-id=xxx.xxx.xxx.xxx templates=ASxxxxxx as=xxxxxx multihop=yes address-families=ipv6 add-path-out=all 
     output.redistribute=static,bgp .filter-chain=out_xxxxxxxx .no-early-cut=yes 
     input.filter=REJECT 
You do not have the required permissions to view the files attached to this post.
 
User avatar
mrz
MikroTik Support
MikroTik Support
Posts: 7042
Joined: Wed Feb 07, 2007 12:45 pm
Location: Latvia
Contact:

Re: [BGP] add-path-out seems to be ignored

Mon Dec 19, 2022 11:37 am

bgp multipath / add-path is not implemented.
 
Gunni
just joined
Topic Author
Posts: 4
Joined: Fri Feb 11, 2022 5:25 am

Re: [BGP] add-path-out seems to be ignored

Tue Dec 20, 2022 10:54 pm

So Mikrotik added an option, that does absolutely nothing...

Not even a little warning in the logs when I use it?
Warning: add-path-out is not implemented?
Or, even not showing it on prod builds?
 
easyswiss
just joined
Posts: 13
Joined: Tue Mar 08, 2016 9:49 pm

Re: [BGP] add-path-out seems to be ignored

Wed Dec 21, 2022 10:42 pm

We have the same problem. We bought (and got) a lot of CCR2216 and we can't use them.
I think Mikrotik doesn't know that as-override, remove-private-asn and add-path-out are the 3 most used bgp tools.
There are a lot of filtering options in Routeros 7.6, but the most important thing in BGP is to announce correctly the routes and not to filter.
[xxx@xxx-xxx] > /system resource print
                   uptime: 1d20h21m59s
                  version: 7.6 (stable)
               build-time: Oct/17/2022 10:55:40
         factory-software: 7.1.3
              free-memory: 14.7GiB
             total-memory: 15.9GiB
                      cpu: ARM64
                cpu-count: 16
                 cpu-load: 25%
           free-hdd-space: 83.6MiB
          total-hdd-space: 129.6MiB
  write-sect-since-reboot: 195560
         write-sect-total: 1173279
               bad-blocks: 0%
        architecture-name: arm64
               board-name: CCR2216-1G-12XS-2XQ
                 platform: MikroTik
 
User avatar
Splash
Member Candidate
Member Candidate
Posts: 206
Joined: Fri Oct 16, 2015 10:09 am
Location: Johannesburg, South Africa

Re: [BGP] add-path-out seems to be ignored

Fri Jul 21, 2023 11:45 am

Something I found works for me on the CCR2004's is to set the CPU affinity to main under the template for all BGP peering sessions.
/routing bgp template
set input.affinity=main output.affinity=main

Who is online

Users browsing this forum: No registered users and 19 guests