[ale] Static IP became DHCP IP

[David Tomaschik]

On 10/24/2011 07:36 PM, JD wrote:
> A few weeks ago I brought up an Ubuntu 10.04 server KVM client to run a
> Redmine instance.  We use thin as the app server with nginx running on a
> different machine doing the reverse proxy and SSL stuff.
>
> I don't have "am-I-alive" monitoring setup yet, so I manually check to
> see if the service is working. It isn't quite a production system yet.
> Today, nginx said the back end was down.  No ping, no ssh available from
> inside the LAN.  Pulled up a console, logged in fine. The static IP had
> been changed .. somehow into a DHCP realm.  Huh?  Checked the
> /etc/network/interfaces file and it clearly showed the static IP with
> all the correct settings. For my sanity, I restarted the networking and
> that put it back on the desired static IP, nginx found and started
> serving the appropriate pages ... all seems good ....
>
> Except I'd like to know how it got moved from the static IP (verified
> working yesterday - had to help an end user login) to the DHCP IP
> sometime today.
>
> I've never had to disable DHCP on previous static IP hosts, just
> changing the interfaces file has been enough. It appears that the DHCP
> client script decided to run and reset the IP address.   The
> /etc/network/interfaces hasn't been modified since 10/1 - when the
> system was setup. the static IP has been working all this month - no
> reboots.
>
> I've checked log files, crontabs, auth.log, dmesg, syslog and don't see
> anything funny.
>
> Redmine and thin run as user "redmine" - no privileges and on a high
> port.  I've never seen this behavior before.
>
> Any ideas what I misconfigured, if anything?
>
NetworkManager's not installed/running, is it?  Although it's supposed
to ignore interfaces that have a configuration in
/etc/network/interfaces, I've seen it do odd things.

-- 
David Tomaschik, RHCE, LPIC-1
System Administrator/Open Source Advocate
OpenPGP: 0x5DEA789B
http://systemoverlord.com
david at systemoverlord.com