point-to-point interface routes marked inactive

[Nick Tait]

After upgrading to Ubuntu 15.04, I discovered that the network routes that were supposed to be added by zebra for my openvpn tun0 interface weren't there. On further investigation it seems that quagga is getting the wrong IP details for this point-to-point interface. FYI This openvpn interface (tun0) uses the 'p2p' topology in openvpn configuration.

When I first set this up over a year ago I made some notes that included the output from the "show ip route" command (from 'telnet localhost zebra' session) which showed:

S>* 192.168.10.0/24 [1/0] via 192.168.10.25, tun0
C>* 192.168.10.25/32 is directly connected, tun0

However since upgrading to Ubuntu 15.04, the equivalent lines now show:

S 192.168.10.0/24 [1/0] via 192.168.10.25 inactive
C>* 192.168.20.25/32 is directly connected, tun0

The key difference here is the IP address in the 'C' line. In the former case the IP address is the remote end of the tunnel, 192.168.10.25, which is correct. In the latter case, it is the IP address of the local end of the tunnel, 192.168.20.25. Consequently, the route in the 'S' is marked inactive and therefore doesn't get added to the routing table.

Here are the details for the tun0 interface from ifconfig:

tun0 Link encap:UNSPEC HWaddr 00-00-00-00-00-00-00-00-00-00-00-00-00-00-00-00
          inet addr:192.168.20.25 P-t-P:192.168.10.25 Mask:255.255.255.255
          UP POINTOPOINT RUNNING NOARP MULTICAST MTU:1500 Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:50 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:100
          RX bytes:0 (0.0 B) TX bytes:14080 (14.0 KB)

BTW I also have another openvpn interface (tun1) which uses 'subnet' topology (rather than 'p2p'), and it is working fine.

ProblemType: Bug
DistroRelease: Ubuntu 15.04
Package: quagga 0.99.23.1-1
ProcVersionSignature: Ubuntu 3.19.0-15.15-generic 3.19.3
Uname: Linux 3.19.0-15-generic x86_64
ApportVersion: 2.17.2-0ubuntu1
Architecture: amd64
Date: Wed Apr 29 20:47:06 2015
ExecutablePath: /usr/lib/quagga/zebra
InstallationDate: Installed on 2014-05-04 (360 days ago)
InstallationMedia: Ubuntu 14.04 LTS "Trusty Tahr" - Release amd64 (20140417)
ProcEnviron:
 PATH=(custom, no user)
 LANG=en_NZ.UTF-8
 LANGUAGE=en_NZ:en
SourcePackage: quagga
UpgradeStatus: Upgraded to vivid on 2015-04-26 (3 days ago)
mtime.conffile..etc.quagga.daemons: 2014-06-08T22:14:02.457222

[Nick Tait (nick.t)]

This bug appears to be fixed now. My Quagga package version is: 0.99.24.1-2
:-)