Hi Ondrej,
Do you have more information and/or tips for me, by chance?
As others wrote, you could do periodic pinging by e.g. fping and enable/disable a static protocol using birdc (birdc disable XXX). See the attached script, which does something like that and estimating packet loss.
Thank you very much for that script. I have two additional questions about this: 1) Why do you stop the whole routing process if the ISP is down? Isn't there a chance to "only" stop distributing the default-route and keep the OSPF process? If yes, how am I able to realize that? 2) If 1) isn't possible, is there a way to check and count incoming routes from eBGP so that the router sees that the connection works and distributes the default-route after the check? My goal is to only stop distributing the default-route and not to kill any routing-protocol such as OSPF. Thanks in advance. -----Ursprüngliche Nachricht----- Von: Ondrej Zajicek [mailto:santiago@crfreenet.org] Gesendet: Samstag, 5. Dezember 2015 16:34 An: Rohrmann Sascha Cc: bird-users@network.cz Betreff: Re: default route via OSPF depending on the ISP On Thu, Dec 03, 2015 at 03:12:10PM +0000, Rohrmann Sascha wrote:
Well, you could use static default-route and 'check link' option, but that will help you only in the third case, not in the second one. For the second case, you must have some other way to establish whether ISP is up or down, either by running some routing protocol between you and ISP, or running BFD session.
Just as you said, that will only help me in the third case. In which way should BFD be able to accomplish my goal? In my understandings BFD only checks if the link is available. If this isn't given, BFD tells Bird this problem.
BFD checks whether specified/destination IP is available (but it also must run BFD). Therefore both link and host must be up.
Second problem is, not every ISP supports BFD yet because BFD is kinda new.
That is true, and also BFD-controlled static routes are only in devel version of BIRD, not in v1.5.0
I was thinking about a simple ping which checks the availability of the opposite party. Am I able to include a simple shell script in bird?
No
Do you have more information and/or tips for me, by chance?
As others wrote, you could do periodic pinging by e.g. fping and enable/disable a static protocol using birdc (birdc disable XXX). See the attached script, which does something like that and estimating packet loss.
I was thinking about the bfd protocol, but bfd is kinda new and you can't run more than one instance in bird. Well, is there any reason why to run multiple BFD instances in BIRD?
Well... you could create one bfd instance for one single interface. Furthermore you could then check the availability for e.g. my problem instead of checking all BFD instances.
I don't understand here. -- Elen sila lumenn' omentielvo Ondrej 'Santiago' Zajicek (email: santiago@crfreenet.org) OpenPGP encrypted e-mails preferred (KeyID 0x11DEADC3, wwwkeys.pgp.net) "To err is human -- to blame it on a computer is even more so."