Name or service not known
|This article/section is a stub — probably a pile of half-sorted notes, is not well-checked so may have incorrect bits. (Feel free to ignore, fix, or tell me)|
...an error, with an errno of -2.
A host name lookup problem, and one that can have many different causes.
Before digging in to diagnose the problem, check the same thing on a different computer. If any test fails on other computers on the same network, it's likely to be a problem external to you (e.g. DNS server or proxy failing, or such).
Possible causes / things to look at
If a hostname lookup is being done that makes no sense, for example gethostbyname() on an URL instead of a hostname.
host can't look up itself
If one of the following fails (replacing hostx or your favorite resolving utility):
hostx localhost hostx `hostname`
...then it's likely your /etc/hosts is broken, or possibly the hostname you have set (there are some extra details to this when you set an FQDN as your hostname).
nameserver / proxy trouble
- If the above work but things like:
hostx google.com hostx yourisp.com
...all fail, then it might be DNS trouble - including not having a DNS server set (in *nices, look at /etc/resolv.conf)
- Another reason for things not to work -- or sometimes for them to have weird patterns of working and not working -- can be that your /etc/nsswitch.conf is malconfigured, or configured to include something that does not work consistently (see in particular its hosts: line).