Not a 100% fix, but it's good enough...
I've basically been trying to be too clever!
The only way to make an IP address 'stay up' even if the interface has
gone away is to use a loop back address and advertise a route to that.
This configuration is getting too complicated!
Just using OSPF to listen for routing updates provides the redundancy that
is required for the configuration. In the event of a network failure a
route is learned through the other interface.
Any TCP based services give up at this point as the source address has
changed. However any new session will be fine.
UDP just carries on.
UDP is the important protocol in this case as the service we need to
protect is the NFS client.
I'd still be interesteed to hear of any improvements to my configuration.
The gated.conf file looks like this:-
interface all {
passive;
};
traceoptions "/usr/tmp/gated.log" replace size 100k files 2 general ;
routerid 192.168.100.100;
ospf yes {
traceoptions lsatransmit;
backbone {
interface tu;
};
} ;
!---------------------------------------------------------------------------
= Jonathan Nicholson - Team Leader : System Support "Special Projects" =
= The Sanger Centre, Wellcome Trust Genome Campus, Hinxton, Cambs, CB10 1SA =
= Email: jjn_at_sanger.ac.uk -=- Tel: 01223 834244 x4987 -=- Fax: 01223 494919 =
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---------- Forwarded message ----------
Date: Thu, 12 Dec 2002 20:38:46 +0000 (GMT)
From: Jonathan Nicholson <jjn_at_sanger.ac.uk>
To: Alpha OSF managers <tru64-unix-managers_at_ornl.gov>
Subject: Re: OSPF Routing updates
Further to this, I've worked out why this doesn't work, but not how to fix
it!
The DS10s are advertising themselves as a route to the 192.168.101.0/24
network rather than just the host route (192.168.101.100/32)
When the switch is still active it has a higher priority and so will
perform the routing for the network. When the switch fails (power off)
then the ds10 becomes the router, the reason it's only working part of the
time is because there's another node that's trying to do the same thing.
What I need to work out how to do is to make gated only advertise a host
route to the other interface rather than a route to the whole subnet.
Regards,
Jonathan
On Thu, 12 Dec 2002, Jonathan Nicholson wrote:
> Hi,
>
> I'm trying to make a reliable network configuration using OSPF.
>
> The plan is to use the 2 interfaces on a DS10 into different networks &
> switches:-
> ______
> _( )_
> (_ OSPF _)
> / (______) \
> / \
> / \
> ---------- ----------
> | Switch 1 | | Switch 2 |
> | 100.1 | | 101.1 |
> ---------- ----------
> | |
> | --------------------- |
> | | DS10 | |
> +-+ tu0 192.168.100.100 | |
> | 192.168.101.100 tu1 +-+
> ---------------------
>
>
> The idea is that should switch 2 fail the DS10 will announce a host route
> to 192.168.101.100 vi 192.168.100.100 which should be propergated through
> the network.
>
> The I've got the DS10 configured as an IP router (iprsetup -s) and the following
> configureation for gated:-
>
> # Create 2 trace files 100k each in /usr/tmp/gated.log (replace .0, .1...)
>
>
> traceoptions "/usr/tmp/gated.log" replace size 100k files 2 general ;
>
> routerid 192.168.100.100;
>
> ospf yes {
> traceoptions lsatransmit;
> backbone {
> interface tu;
> };
> } ;
>
>
> However it doesn't seem to work quite right.
>
> Under certain failure conditions (ie turning the switch off) it works 40% of
> the time!
>
> Has anyone done any configuraiton of this type?
>
> Regards,
>
> Jonathan
>
>
>
>
> !---------------------------------------------------------------------------
> = Jonathan Nicholson - Team Leader : System Support "Special Projects" =
> = The Sanger Centre, Wellcome Trust Genome Campus, Hinxton, Cambs, CB10 1SA =
> = Email: jjn_at_sanger.ac.uk -=- Tel: 01223 834244 x4987 -=- Fax: 01223 494919 =
> ----------------------------------------------------------------------------
>
--
!---------------------------------------------------------------------------
= Jonathan Nicholson - Team Leader : System Support "Special Projects" =
= The Sanger Centre, Wellcome Trust Genome Campus, Hinxton, Cambs, CB10 1SA =
= Email: jjn_at_sanger.ac.uk -=- Tel: 01223 834244 x4987 -=- Fax: 01223 494919 =
----------------------------------------------------------------------------
Received on Mon Dec 16 2002 - 12:16:55 NZDT