Hi, I’m running on 3.9.0-3 and if I go to the system update webUI I get the same error as stated above…no way to change the update channel or to perform any update (beside the error the page stays white)? Any idea?
Also running yum update from the terminal gives the following message 
[root@rockstor ~]# [root@rockstor ~]# yum update
Existing lock /var/run/yum.pid: another copy is running as pid 21608.
Another app is currently holding the yum lock; waiting for it to exit…
The other application is: yum
Memory : 34 M RSS (419 MB VSZ)
Started: Fri Jun 16 12:51:32 2017 - 02:34 ago
State : Sleeping, pid: 21608