On Tue, Aug 14, 2018 at 2:27 PM Ondrej Zajicek <santiago@crfreenet.org> wrote:
On Mon, Aug 13, 2018 at 03:14:10PM +0200, Jakub Nowacki wrote:
Hi,
I'm running BIRD on Arista which allows access to Linux bash. I'm having issue with running multihop BFD session on it and I believe it's related to port being already binded.
bash-4.3# netstat -tulpen | grep 4784
udp6 0 0 :::4784 :::*
0 4269 -
Hi
I thing 4269 here is PID, what is the process? netcat should return the process name, which is not here, but perhaps it is some limited variant of netcat. Maybe BFD is implemented in control plane on Arista, so it collides on kernel level?
4269 is Inode, netstat for some reason doesn't show PID/process name for ports related to BFD on Arista. This seems to be Arista thing not Bird, so probably that's not a place to investigate this here. Also, there should be an error message in the BIRD log related to bind
errors.
I haven't seen any error messages in log, perhaps logging level were not set for it. I'll double check it.
I couldn't find any configuration option for BFD to change port being used, but maybe there is one?
There is no such option. Perhaps we should add it, as BGP and RIP also have port option.
That would be super helpful. I could create Pull Request for it, but I've only written in C++ years ago, never actually touched plain C, it can take me some time.
Perhaps anyone run into similar issue and have a workaround?
As a workaround you can recompile BIRD with changed BFD_MULTI_CTL_PORT in proto/bfd/bfd.h file.
That's what I did. After changing port to arbitrary value, which is not taken on Arista it started to work. So it seems that BFD is failing due to Arista OS.
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