Unpleasant feature of Ubuntu Linux for system administrators

Reorganizing the disk space for storing information on a production server running Ubuntu Linux opened a very interesting feature: the / var / run directory must be on the root file system!
I assembled the RAID, transferred / var to it and entered the mount point. When the system was booted, very strange things began to be observed: most of the daemons automatically stopped loading at startup, the network did not start (no / var / run / network is created) and similar anomalies. At the same time, viewing the logs does not give anything concrete.
Solution: create / var / run (root: root, drwxr-xr-x) and / var / lock (root: root, drwxrwxrwt) directories on the root filesystem ( / ), which will give a normal start, and immediately after starting / var, located on the array will be correctly included in the system.