Depending on which version of node exporter you are using, one of the following options will work.
Node exporter version go1.14.4
/usr/local/bin/node_exporter \
--collector.systemd \
--collector.system.unit-whitelist=(graylog-server|mongod|elasticsearch).serviceNode exporter version go1.15.8
Since the option “collector.system.unit-whitelist” was deprecated, the syntax has changed to “collector.systemd.unit-include”.
Note that there might be a bug in this version such that it won’t work if you put an equal (=) sign before the value:
/usr/local/bin/node_exporter \
--collector.systemd \
--collector.systemd.unit-include "(graylog-server|mongod|elasticsearch).service"PAM, or Linux Pluggable Authentication Modules
PAM stacks are not very easy to read. If you made a change but didn’t test it well, it might not work as expected. Or worse, you may end up exposing a vulnerability in your authentication mechanisms.
Here are my notes about the 3 terms in the PAM stack:
required: keeps going (despite success or failure).
sufficient: it stops (disregards what’s below it) when succeeds. It will only be successful if no previous ‘required’ items have failed.
requisite: if this fails, stops and return failure
