Category Archives: Uncategorized

Gnome 3 (Fedora 27) Screen Lock Timeout

Gnome 3 doesn’t appear to offer any GUI control over the screen lock timeout.

So, to get current values:-

[snetting@lapper ~]$ gsettings get org.gnome.desktop.session idle-delay
uint32 300
[snetting@lapper ~]$ gsettings get org.gnome.desktop.screensaver lock-delay
uint32 0

And to set:-

[snetting@lapper ~]$ gsettings set org.gnome.desktop.session idle-delay 600

idle-delay is the time taken to blank the screen.
lock-delay is an additional delay before locking.

OSEv3 Node Utilisation

A quick and dirty script to query all nodes for utilisation data:-


printf "%-12s %-25s %-4s %-15s %-20s %-18s %-8s \n" "NODE" "STATE" "PODS" "CPU Req" "CPU Lim" "Memory Req" "Memory Lim"
oc get nodes --show-labels | grep user | while read NODE STAT stuff
printf "%-12s %-25s %-5s " $(echo $NODE | cut -f1 -d. ) $STAT $(oadm manage-node --list-pods $NODE 2> /dev/null | sed '/^NAME.*/d' | wc -l)
printf "%-7s %-7s %-7s %-12s %-12s %-5s %-12s %-5s\n" $(oc describe node $NODE | grep -a2 "CPU Requests" | tail -1)

Docker Panic, CMD and Hashbang

Noticed issue when rebuilding dockerfile and running image:-

panic: standard_init_linux.go:178: exec user process caused "exec format error" [recovered]
	panic: standard_init_linux.go:178: exec user process caused "exec format error"

goroutine 1 [running, locked to thread]:
panic(0x6f3080, 0xc4201393b0)

Did much digging, identified that when specifying a script as a CMD in the Dockerfile, this script now requires a proper hashbang (aka shebang) or the above panic results.

rm -rf /run/httpd/* /tmp/httpd*
exec /usr/sbin/apachectl -DFOREGROUND

Rebuilding the docker image with –no-cache option ensures the updated file is included.

Dummy java loop/sleep for test of init scripts

A dummy java executable (actually a jar) was required to develop init scripts without access to the client’s application.   The process of creating a Java ‘sleep’ application and wrapping within a ‘jar’ complete with manifest was not obvious to me.  The ‘thread.sleep’ also didn’t work as I expected, requiring an additional exception handler.  Not to mention the requirement for the manifest to require multiple new lines before being syntactically correct (and no report otherwise when incorrectly parsed, except ‘no main manifest attribute’ when attempting to run).  Why Java, WHY?

The following tgz contains both the compiled java executable plus source, manifest and instructions to build / compile the jar should the wait time (default 100 seconds) need to be modified.

WaitLoop.tgz (source and executable tgz)
WaitLoop (Github Project)

The .jar can be executed with:-

java -jar WaitLoop.jar