Claudio Jeker wrote:
On Thu, Jan 29, 2009 at 02:57:09AM -0500, Daniel Ouellet wrote:
Hi,
I am curious as to if this is really normal. I would say not, but may be
I miss something, or miss understood something. All active and
configured interfaces does show up in the fib table as they should and
same for the standard loopback on as well as below:
Loopback interface lo0 at 127.0.0.1/8 is present in the fib table:
# ifconfig lo0
lo0: flags=8049<UP,LOOPBACK,RUNNING,MULTICAST> mtu 33160
groups: lo
inet 127.0.0.1 netmask 0xff000000
inet6 ::1 prefixlen 128
inet6 fe80::1%lo0 prefixlen 64 scopeid 0x6
# bgpctl s f 127.0.0.0
flags: * = valid, B = BGP, C = Connected, S = Static
N = BGP Nexthop reachable via this route
r = reject route, b = blackhole route
flags destination gateway
*S r 127.0.0.0/8 127.0.0.1
So, I would assume that configuring and additional loopback interface in
hostname.lo2 for example should show up the same way on reboot just like
any other interfaces on the router specially if it is showing up in the
ipconfig as well no? Why is it not present in the fib table?
Example:
# ifconfig lo2 inet 10.0.0.1 netmask 255.255.255.0
# ifconfig lo2 up
#
# ifconfig lo2
lo2: flags=8049<UP,LOOPBACK,RUNNING,MULTICAST> mtu 33160
groups: lo
inet 10.0.0.1 netmask 0xffffff00
Should show up the same way in the fib table no?
# bgpctl s f 10.0.0.0
flags: * = valid, B = BGP, C = Connected, S = Static
N = BGP Nexthop reachable via this route
r = reject route, b = blackhole route
flags destination gateway
*SN 0.0.0.0/0 66.63.0.145
Is there something I am missing?
This is on 4.4
It does but not when the interface is added during runtime. Bgpd is
missing the necessary hooks to get new interface addresses during runtime.
This is an item on my todolist.
The reason I asked is because for example I was testing configuration
using loopback interface and when I reboot and I do not run bgpd I can
ping the loopback interface no problem, however if I reboot and bgpd run
I can still ping it, however it will time out regularly and sometime be
dead for as much as a minutes in worst case and go up/down and the bgp
sessions with the loopback interface will flap. Not always but sometime
it does. I just find out by luck I guess when I work doing constant
ping. if I stop bgpd, all goes normal and no lost packets what so ever,
if I restart bgpd, then sessions come up, can stay up for a long time no
problem, but ping time to time to the same loopback will fail and it
will happened that some bgp sessions will flap. I don't recall have seen
this on previous version of bgpd and the configuration stayed the same,
just upgrade to 4.4. It's been running for a few months, but I see rare
flaps and digging in it, that's what I found.
So, I was curious as to if any loopback interface shouldn't be use with
bgpd, witch I am pretty darn sure it can be done like any other bgp router.
If I configure the sessions with the interface itself, it's good, if I
configure sessions with the loopback, I could see time to time flap and
ping fail to the loopback interface.
Somewhat weird.
Daniel
