Posts Tagged ‘precise’

wget, busybox, ipv6…

Thursday, February 28th, 2013

In our work environment, we use pxe and preseed to roll out Ubuntu 12.04 installations. In the late command, we even splat puppet standalone and a subversion repository on it. Works nicely.

Last week however, this tested routine stopped working in a very early stage – when wget in busybox tries to figure out which release of Ubuntu to pull from the mirror server.

The actual code line was: wget -q ftp://somehost.domain.local/file -O – | grep -E ‘^(Suite|Codename):’
This line didn’t return anything, so the installation got stuck. On my pc, the same line returned something useful.

In the end, the problem was that ipv4 and ipv6 were configured automatically and wget in busybox prefers ipv6 over ipv4 but if wget fails, it does not try again with ipv4. And since it comes with busybox, you can’t force a protocol family (see ‘man wget’ for further infos).

The solution was to supply another kernel parament in the pxe configuration: ipv6.disable=1

There are some users who report that this line does not work for them. Maybe they got the spelling slightly wrong or they put it at the wrong place but with this additional parameter, our setup is working again.

The sad thing about this is that this problem was already bug-reported in 2007 but the status was put to ‘wontfix’ and closed. Way to go 🙁

And I only wasted about 6 hours of working hours for that crap.