make dnsmasq log easy to access and include it into diagnostic snapshots

[Alexei Sheplyakov]

dnsmasq logs are necessary for debugging nodes' boot and networking problems.
However the log file (/var/log/dnsmasq.log) is hidden in the cobbler container and is not included
into the diagnostic snapshots.

[Alexander Gordeev (a-gordeev)]

I'm wondering, is it still valid?

as I've found a lot of dnsmasq.log files across various snapshots. Seems it was included into snapshot from the ancient version of fuel.

File is hidden at <master_IP>/var/log/docker-logs/dnsmasq.log

http://paste.openstack.org/show/473458/

Perhaps, you guys are interested in entirely another dnsmasq log file. Aren't you?

[Ihor Kalnytskyi (ikalnytskyi)]

Thanks Alexander, looks like you're right here. I can confirm that /var/log/docker-logs/dnsmasq.log on master node (and inside diagnostic snapshot) is the same as /var/log/dnsmasq.log in cobbler container.

Proof (see inode index):

    [root@fuel ~]# ls -i /var/log/docker-logs/dnsmasq.log
    392517 /var/log/docker-logs/dnsmasq.log

    [root@fuel ~]# dockerctl shell cobbler ls -i /var/log/dnsmasq.log
    392517 /var/log/dnsmasq.log

Move it to Invalid.