As you suggest, update and notification packets will also reset the hold timer. Only sends keepalives in abscence of other packets.
Jody On Sun, 3 Mar 2019 at 04:58, <[email protected]> wrote: > Hi, > > Spot on. Thanks. > > I had a thought that it could be an mtu issue but discounted it as a > keepalive is such a small packet. > > I wonder therefore if when it is exchanging routes it does not bother > with keepalives, which makes sense as there not needed as the routers > are exchanging BGP packets. I was also only seeing a very small number > of routes being recieved by the customer end. > > A BGP route packet is obviously bigger and therefore was too big to be > received by the router with the lower mtu. > > Thanks for the help. Spot on!! > > Regards > > On 2019-03-03 03:56, Job Snijders wrote: > > Hi, > > > > Please confirm that the MTU settings on both the layer-2 and layer-2 > > components of your topology align with each other. An MTU mismatch may > > result in some larger BGP packets never ariving, resulting in the > > behaviour you see. > > > > Kind regards, > > > > Job > > > > On Sun, Mar 03, 2019 at 03:45:05AM +0000, [email protected] wrote: > >> Evening All > >> > >> Having a really strange one here, where keepalive messages seem to be > >> getting lost between 2 MX80 routers doing external BGP to each other. > >> > >> The BGP session comes up ok, and then drops 30 seconds later as the > >> other > >> side does seem to be recieving the keepalive. > >> > >> Now to make things more strange is I have seen this happen before > >> recently > >> with another pair of mx80's one of which is talking to one of the > >> current > >> pair fine. > >> > >> So we have MX80's at ISP1-4 > >> > >> ISP1-ISP2 is having this issue, these are both running old versions of > >> Junos > >> and had previously been put down to this and the link had been given > >> up on. > >> > >> ISP2-ISP3 is working fine and has been for nearly a year > >> > >> Now we have ISP3-ISP4 having the same issue. Both these routers are > >> running > >> the latest version of JUNOS. > >> > >> Topology of ISP1-ISP2 is > >> > >> MX80 <-> Ubiquiti 10G <-> Extreme 10G <-> MX80 > >> > >> > >> Topology of ISP2-ISP3 > >> > >> MX80 <-> Extreme 10G(as above) <-> MX80 > >> > >> Topology of ISP3-ISP4 > >> > >> MX80 <-> Juniper EX3300(virtual Chassis <-> MX80 > >> > >> Anyone have any ideas on this as I am drawing a blank. > >> > >> Regards > >> > >> > >
