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I have a KVM host with a bridge configured on eth0 that has a public ip:

auto br0
iface br0 inet static
  address xx.xx.aa.111
  network xx.xx.aa.0
  broadcast xx.xx.aa.255
  gateway xx.xx.aa.1
  bridge_ports eth0
  bridge_stp on
  bridge_maxwait 0
  bridge_fd 0

This host has a guest on it with its own public IP address:

auto eth0
iface eth0 inet static
  address xx.xx.bb.246
  network xx.xx.bb.0
  broadcast xx.xx.bb.255
  gateway xx.xx.bb.1

However, when connecting from the guest with xx.xx.bb.246 via ssh to another host, auth.log shows xx.xx.aa.111 instead of xx.xx.bb.246. This troubles BIND9's zone transfers and notifies because other servers only allow connections from xx.xx.bb.246 (the guest) and not from xx.xx.aa.111 (the host), according to syslog.

ip route show of host:

xx.xx.aa.0/24 dev br0  proto kernel  scope link  src xx.xx.aa.111 
default via xx.xx.aa.1 dev br0 

and for the guest:

xx.xx.bb.0/24 dev eth0  proto kernel  scope link  src xx.xx.bb.246 
default via xx.xx.bb.1 dev eth0

Does anyone have an idea on how to solve this problem?

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1 Answer 1

up vote 0 down vote accepted

Ah, stupid little thing that kept me busy for hours. There were two interfaces, one internal and one external on the guest. traceroute showed that outgoing connections were made through the internal network.

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