Draining state means that no new jobs will be accepted to the queue. This will not however stop already queued jobs from running.
The draining status is automatically derived by the GIP plugin if queue enabled attribute is set to False. Therefore:
qmgr -c 's q QUEUNAME enabled = False'
To get queue back online:
qmgr -c 's q QUEUNAME enabled = True'
Dynamic information is generated by GIP plugins and providers that reside in
/opt/glite/etc/gip/plugin /opt/glite/etc/gip/provider
just run them under edguser to see what information will reach infosystem.