VyOS eBGP / iBGP flaps

bgp

#1

Hello everyone,
I need some help with VyOS and some weird issue that I have stumbled upon. I have two instances, which are running BGP. Both instances have other BGP peers and they work fine. They receive hundreds of thousands of prefixes without a problem. However, when I try to make them peer together (either via iBGP or via BGP confederations), one of the two (at random), in “show ip bgp summary” starts receiving prefixes, and by running the command multiple times, I can see them go up… 100k, 200k, 300k, … However, when they reach the full 700k-something of the IPv4 table, the connection state moves to “Clearing”, and then “Idle”, and then all over again…

CPU usage is at 50% all the time this happens, and prefixes are transferred between the two routers all the time.

Both routers have “soft-reconfigure inbound” in their “neighbor” block and “remote-as”, and that’s it.

It happens both using iBGP (same private AS, same confederation “peer-id”), as well as CFBGP (different private AS, same confederation “peer-id”, added as “peers”).

Any idea what might be causing this?

Thanks!


#2

Hi,
share configs,
otherwise it´s very difficult to judge


#3

Here you can see from RTR1, in RTR2 it’s the same one in reverse (other public peer, RTR1 as confed. peer).

protocols {
    bgp 65100 {
        address-family {
            ipv6-unicast {
                aggregate-address 2001:db8::/40 {
            }
            network 2001:db8::/48 {
            }
        }
    }
    aggregate-address 192.0.2.0/24 {
    }
    maximum-paths {
        ebgp 3
    }
    neighbor 10.10.10.10 {
        description TENTENTENTEN
        password foobar
        remote-as 100
        soft-reconfiguration {
            inbound
        }
    }
    neighbor 10.20.10.20 {
        description CONFPEERA
        remote-as 65200
        soft-reconfiguration {
            inbound
        }
    }
    neighbor 2001:2001::1 {
        address-family {
            ipv6-unicast {
                soft-reconfiguration {
                    inbound
                }
            }
        }
        description V6
        remote-as 100
        soft-reconfiguration {
            inbound
        }
    }
    network 192.0.2.0/24 {
    }
    parameters {
        confederation {
            identifier 200
            peer 65200
        }
        router-id 1.2.3.4
    }
    }
}

#4

Hi daknob,

Did you check free memory?

Oleksandr Mamenko


#5

Hello and thanks for the reply.

Yes, the memory is not utilized in full, there’s plenty of head room. It also happens w/o soft-reconfiguration, and with iBGP. Also, peering with another AS, will full tables, works fine.


#6

Are you able to upgrade this environment to latest 1.2 rolling?