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Iain Hallam
Asked: 2013-07-31 03:12:24 +0800 CST

How to configure cluster.conf for failover routing two networks?

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I'm routing between an "external" subnet with Internet connectivity and two "internal" subnets, using iptables forwarding on a Linux box running CentOS 6.4:

Single router

I'd like to now duplicate this router into an HA configuration using the Red Hat Cluster Suite (rgmanager and cman):

Router pair

I can get floating IP addresses between the two hosts with this cluster.conf:

<resources>
    <ip address="192.168.1.1" monitor_link="1"/>
    <ip address="192.168.2.1" monitor_link="1"/>
    <ip address="192.168.3.1" monitor_link="1"/>
</resources>
<service autostart="1" name="ha-routing" recovery="restart">
    <ip ref="192.168.1.1"/>
    <ip ref="192.168.2.1"/>
    <ip ref="192.168.3.1"/>
</service>

However, if one of the internal networks goes down, the whole service can't start, effectively taking down the other network as well.

I tried separating the IPs into separate services, both using the external IP:

<service autostart="1" name="ha-routing-a" recovery="restart">
    <ip ref="192.168.1.1"/>
    <ip ref="192.168.2.1"/>
</service>
<service autostart="1" name="ha-routing-b" recovery="restart">
    <ip ref="192.168.1.1"/>
    <ip ref="192.168.3.1"/>
</service>

In this situation, if an internal network fails, the clustered service will shut down, and the external address will be removed anyway, so it still seems to kill the other internal network.

What's the best configuration for the pair to get failover routing for both networks?

cluster

0 Answers