Red Hat Bugzilla – Bug 433846
vpnc hard-coded mtu in tun0 creation
Last modified: 2008-04-03 04:42:18 EDT
Description of problem:
/etc/vpnc/vpnc-script has a hard-coded MTU of 1412 used to bring up the tun0
interface. This is an invalid MTU if the underlying Ethernet interface (i.e.
eth0) already has a lower-than-normal MTU of 1400. vpnc-script should read the
existing MTU from the interface and subtract a certain number of bytes to
determine its MTU instead of hard-coding 1412.
Version-Release number of selected component (if applicable):
Steps to Reproduce:
1. ifconfig eth0 mtu 1400
2. vpnc Config
3. ifconfig tun0 shows mtu 1412, greater than eth0.
4. scp large file over VPN connection and scp will stall
If I edit vpnc-script and replace 1412 with 1300, scp works fine when my eth0
mtu is 1400.
Fixed in rawhide.