[LARTC] failover problems

[LARTC] failover problems

[Tobias Geiger]

Hello LARTC,

I'm testing Failover and i'm getting this problem:

In the moment the device gets deleted (dissapears from /proc/net/dev) e.g.
pppd crashes all RULES regarding this device are flushed.
Is this a known bug/problem (i think so :)
is there a workaround/solution (except adding the rules again in ip-up.d) ?

Thanks in advance

Tobias


_______________________________________________
LARTC mailing list / LARTC@mailman.ds9a.nl
http://mailman.ds9a.nl/mailman/listinfo/lartc HOWTO: http://lartc.org/

Re: [LARTC] failover problems

[Tobias Geiger]

addition:

to be precisly: the problem is i have several nexthops (e.g. ppp0 +eth1
+eth2) for the same route and this WHOLE Route is deleted, although only
the ppp0-device dissapears...
and i cannot add several entries in different tables, cause this seems not
to do failover

> Hello LARTC,
>
> I'm testing Failover and i'm getting this problem:
>
> In the moment the device gets deleted (dissapears from /proc/net/dev)
> e.g. pppd crashes all RULES regarding this device are flushed.
> Is this a known bug/problem (i think so :)
> is there a workaround/solution (except adding the rules again in
> ip-up.d) ?
>
> Thanks in advance
>
> Tobias
>
>
> _______________________________________________
> LARTC mailing list / LARTC@mailman.ds9a.nl
> http://mailman.ds9a.nl/mailman/listinfo/lartc HOWTO: http://lartc.org/



_______________________________________________
LARTC mailing list / LARTC@mailman.ds9a.nl
http://mailman.ds9a.nl/mailman/listinfo/lartc HOWTO: http://lartc.org/

Re: [LARTC] failover problems

[Julian Anastasov]

	Hello,

On Tue, 23 Jul 2002,  Tobias Geiger wrote:

> to be precisly: the problem is i have several nexthops (e.g. ppp0 +eth1
> +eth2) for the same route and this WHOLE Route is deleted, although only
> the ppp0-device dissapears...
> and i cannot add several entries in different tables, cause this seems not
> to do failover

	Yes, similar behavior appeared in latest 2.4.19pre kernels,
it looks like a recommendation the users to recreate their routes
because a device in nexthop was unregistsred. Is this true for
your setup?

Regards

--
Julian Anastasov <ja@ssi.bg>

_______________________________________________
LARTC mailing list / LARTC@mailman.ds9a.nl
http://mailman.ds9a.nl/mailman/listinfo/lartc HOWTO: http://lartc.org/

Re: [LARTC] failover problems

[Tobias Geiger]

>
>         Hello,
>
> On Tue, 23 Jul 2002,  Tobias Geiger wrote:
>
>> to be precisly: the problem is i have several nexthops (e.g. ppp0
>> +eth1 +eth2) for the same route and this WHOLE Route is deleted,
>> although only the ppp0-device dissapears...
>> and i cannot add several entries in different tables, cause this seems
>> not to do failover
>
>         Yes, similar behavior appeared in latest 2.4.19pre kernels,
> it looks like a recommendation the users to recreate their routes
> because a device in nexthop was unregistsred. Is this true for
> your setup?
>

Yes. i used 2.4.19pre-10 kernel.
This behaviour affects only ppp-devices (never tried ippp but i guess it's
the same)

i also wondered, why failover doesn't work when using different
route-entries for each nexthop...

another confusing thing: using "nexthop via dev ppp0" in a table made me
think that i don't need a gateway address at all... but unfortunatly
that's no the case :(seems that ip searches the gateway address itself so
that after appp-reconnect (where i get another gateway address) the table-entries
aren't valid anymore.

Thanks

Tobias



_______________________________________________
LARTC mailing list / LARTC@mailman.ds9a.nl
http://mailman.ds9a.nl/mailman/listinfo/lartc HOWTO: http://lartc.org/

Re: [LARTC] failover problems

[Julian Anastasov]

	Hello,

On Wed, 24 Jul 2002,  Tobias Geiger wrote:

> Yes. i used 2.4.19pre-10 kernel.
> This behaviour affects only ppp-devices (never tried ippp but i guess it's
> the same)
>
> i also wondered, why failover doesn't work when using different
> route-entries for each nexthop...

	Hm, the kernel can not perform failover for NOARP devices
that are always in UP state. It is possible only for ARP devices
and for default routes with same metric. But if the first route
is automatically deleted from kernel the 2nd one will be used. No?

> another confusing thing: using "nexthop via dev ppp0" in a table made me
> think that i don't need a gateway address at all... but unfortunatly
> that's no the case :(seems that ip searches the gateway address itself so
> that after appp-reconnect (where i get another gateway address) the table-entries
> aren't valid anymore.

	The "via GW" syntax is not mandatory for ppp devices, you
can use only "nexthop dev ppp0", just remove this "via", you have
syntax error. As for ppp devices, it is recommended your scripts
to recreate the multipath routes to contain nexthops only for
valid ppp devices (for which you have established link). As you see,
the new kernels delete the multipath route for you, so you can't
rely on permanent multipath route (I assume the ppp devices really
pass unregistration). Even in the old kernels you have to recreate
the route because when one ppp devices is registered again its
nexthop status does not change, it remains dead.

> Thanks
>
> Tobias

Regards

--
Julian Anastasov <ja@ssi.bg>

_______________________________________________
LARTC mailing list / LARTC@mailman.ds9a.nl
http://mailman.ds9a.nl/mailman/listinfo/lartc HOWTO: http://lartc.org/