Ubuntu 18.04 includes check-mk in the repository version but it is an older version 1.2.8 (at the time of writing). Download check mk raw (get the latest stable URL from the website) : wget... » More
In the update from iDRAC 8 to iDRAC 9 it has been infuriating searching the 'Storage' menu only to discover that the storage is managed under 'Configuration > Storage Configuration' I'm convinced the user experience could be better! At the very... » More
Journald logs can be cleared by timescale or size as follows.
Keep only 5 days worth of logs
journalctl --vacuum-time=5d
Retain only the past 500 MB:
journalctl --vacuum-size=500M
The puppet agent can be disabled from running with: puppet disable "Some message here" And it can be re-enabled with: puppet enable But to check if puppet is currently disabled there is no check command. Instead look for the existence of the... » More
I sometimes want to omit directories from my disk usage (du -sh *) checks. This includes virtual files systems such as proc / dev and also mounts to other filesystems (data in the example below). This is what works for me: du... » More
I was checking the memory on approximately 140 servers using ansible: ansible --user root -k -i servers.list -m shell -a "free -h; mysql" test but the output appears over several lines e.g. server103.domain.dev | SUCCESS | rc=0 >> total used... » More
In a Cloudera cluster we had a few nodes reporting the following error message in the logs under hadoop-cmf-hdfs-DATANODE-whatever.com.log.out The error included: Datanode denied communication with namenode because the host is not in the... » More
On the Windows Domain Controller I checked the current NTP settings with: w32tm /query /configuration I tried a few alternative commands and got errors such as "the rpc server is unavailable". The command that worked was: w32tm /config... » More
I wanted to add some checks to a Windows server and the methods seem to have changed a little over the years. At the moment I have amended the nsclient.ini file on the Windows box with: CheckDisk=1 CheckSystem=1 Then from the Nagios box I can check... » More
Using the Hadoop command we can send fairly regular filesystem commands to navigate HDFS. On Cloudera I am sending commands to port 8020 of the active name node. If you don't have the hadoop command available on your system you need to download hadoop,... » More
Ubuntu 18.04 includes check-mk in the repository version but it is an older version 1.2.8 (at the time of writing). Download check mk raw (get the latest stable URL from the website) : wget... » More
