ctdb w/ per_ip_routing

[Martin Schwenke]

On Sat, 11 Jan 2014 10:41:27 +0100, "Stefan (metze) Metzmacher"
<metze at samba.org> wrote:

> Am 11.01.2014 00:08, schrieb Martin Schwenke:

> >> CTDB_PER_IP_ROUTING_CONF="/etc/ctdb/per_ip_routing.conf"
> >> CTDB_PER_IP_ROUTING_TABLE_ID_LOW=240
> >> CTDB_PER_IP_ROUTING_TABLE_ID_HIGH=246
> >> CTDB_PER_IP_ROUTING_RULE_PREF=100
> >> CTDB_PER_IP_ROUTING_DEBUG=yes
> > 
> > Your LOW and HIGH setting are nice and conservative, so you're unlikely
> > to accidentally stomp on any other tables by accident.  However, if you
> > add IP addresses in the future and forget to expand that range then you
> > might see weird failures.  I'd suggest a wider range somewhere
> > between 1000 and 9000...
> 
> Isn't the table space 0..255 ?

Linux has supported 32-bit routing table IDs since 2006 (2.6.19)...

  commit 9e762a4a89b302cb3b26a1f9bb33eff459eaeca9
  Author: Patrick McHardy <kaber at trash.net>
  Date:   Thu Aug 10 23:09:48 2006 -0700

    [NET]: Introduce RTA_TABLE/FRA_TABLE attributes
    
    Introduce RTA_TABLE route attribute and FRA_TABLE routing rule attribute
    to hold 32 bit routing table IDs. Usespace compatibility is provided by
    continuing to accept and send the rtm_table field, but because of its
    limited size it can only carry the low 8 bits of the table ID. This
    implies that if larger IDs are used, _all_ userspace programs using them
    need to use RTA_TABLE.
    
    Signed-off-by: Patrick McHardy <kaber at trash.net>
    Signed-off-by: David S. Miller <davem at davemloft.net>

ip-route(8) supports this just fine...

However, this is all documented very poorly.  :-(

peace & happiness,
martin