'[quagga-users 10469] Re: Zebra OSPF randomly loosing routes and'

[prev in list] [next in list] [prev in thread] [next in thread] 

List:       quagga-users
Subject:    [quagga-users 10469] Re: Zebra OSPF randomly loosing routes and
From:       Jeremy Jackson <jerj () coplanar ! net>
Date:       2009-03-16 13:18:33
Message-ID: 1237209513.5524.53.camel () ragnarok
[Download RAW message or body]

On Mon, 2009-03-16 at 13:06 +0100, Danilo Godec wrote:
> Hi,
> 
> I have a Linux router (2.4 kernel) with a D-Link 4-port ethernet card.
> LAN side is connected to L3 swithces with redundancy and OSPF dynamic
> routing.

What is the ethernet Speed/Duplex settings?  The DFE-570TX used the
tulip chips which sometimes had trouble with autonegotiation with other
ethernet equipment.  Make sure you're matching settings with the L3
switches and force full duplex/100mbit if the switches are doing this.
Ethernet is *not* plug-and-play even with autoneg.  Check for collisions
or other errors with "ethtool -S eth0"

> Quagga only works if the interface is in 'promisc' mode. We couldn't
> determine whether this is a kernel problem, a network driver (not part
> of the kernel source) or Quagga issue - instead we put the interface in
> promisc mode permanently (using 'ifconfig eth0 promisc').

This sounds like an issue that was in 2.6 briefly, where multicast addrs
got out of sync L3 vs L2 on a NIC.  check "ip maddr show dev eth0" for
the interfaces with OSPF.  It must have matching sets:

	link  01:00:5e:00:00:06
	link  01:00:5e:00:00:05
	link  01:00:5e:00:00:01
	inet  224.0.0.6
	inet  224.0.0.5
	inet  224.0.0.1

Notice the last number exists in both "link" and "inet" lines.  The
above is for an ASBR/ABR, so if yours isn't that topology you might be
missing some of those, (also if it's not elected DR or BDR), but there
should always be a "link" corresponding with the "inet 224.0.0.x" lines.

> Lately the Linux router is loosing routes randomly - not too often, but
> often 'enough'. Apparently this had happened before but it was rare and
> a reboot always solved the problem immediately - whereas now it takes a
> long time before Linux router receives routes from the switches (up to a
> couple of hours).

Have you enabled ospf logging?  You might want to learn some of the
"show ip ospf ..." commands as well.  The first question is if the OSPF
routers are maintaining stable adjacencies.

In ospfd.log, here's one what the restart of an OSPF peer looks like:

2009/03/15 15:27:59 OSPF: AdjChg: Nbr 70.47.139.55 on br0:70.47.139.2:
Full -> Deleted (InactivityTimer)
2009/03/15 15:27:59 OSPF: nsm_change_state(70.47.139.55, Full ->
Deleted): scheduling new router-LSA origination
2009/03/15 15:27:59 OSPF: DR-Election[1st]: Backup 70.47.139.2
2009/03/15 15:27:59 OSPF: DR-Election[1st]: DR     70.47.139.1

peer restarts...

2009/03/15 15:30:37 OSPF: DR-Election[1st]: Backup 70.47.139.2
2009/03/15 15:30:37 OSPF: DR-Election[1st]: DR     70.47.139.1
2009/03/15 15:30:37 OSPF: Packet[DD]: Neighbor 70.47.139.55 Negotiation
done (Slave).
2009/03/15 15:30:37 OSPF: AdjChg: Nbr 70.47.139.55 on br0:70.47.139.2:
Exchange -> Full (ExchangeDone)
2009/03/15 15:30:37 OSPF: nsm_change_state(70.47.139.55, Exchange ->
Full): scheduling new router-LSA origination

with vtysh> show ip ospf neighbor

    Neighbor ID Pri State           Dead Time Address         Interface
RXmtL RqstL DBsmL
70.47.139.1       1 Full/DR           35.532s 70.47.139.1
br0:70.47.139.2          0     0     0

If you keep seeing these when ospfd is configured like below, you have
some basic problems:

log file /var/log/quagga/ospfd.log
router ospf
 ospf router-id 1.2.3.4
 log-adjacency-changes

Note that you will have to telnet to the ospfd to set the log file,
vtysh can't presently do that.

Next, if you have stable adjacency, you might need to enable some of
vtysh> debug ospf {event,lsa,ism}  and watch when routes
appear/disappear.

-- 
Jeremy Jackson
Coplanar Networks
(519)489-4903
http://www.coplanar.net
jerj@coplanar.net

_______________________________________________
Quagga-users mailing list
Quagga-users@lists.quagga.net
http://lists.quagga.net/mailman/listinfo/quagga-users
[prev in list] [next in list] [prev in thread] [next in thread] 