systemctl enable and start service

Most of the times when I want to enable the service, I find myself enabling it immediately or it is vice versa. So, the commands I used to use were:

systemctl enable sshd.service
systemctl start sshd.service

But recently I learned that I do not need the 2 commands and this can be done in single command like below

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systemctl enable --now sshd.service

systemd – start service when you enable it

More often than not for any service, I end up doing :

systemctl enable <service>
systemctl start <service>

But there is shorcut to this. In systemctl command when you enable the service, you can use “–now” to start the service as follows:

systemctl enable --now <service>

quite a timesaver 🙂

journalctl command to see kernel messages

Sometimes, there are just too many messages in journalctl output and it becomes a mystery game to search for the messages you are looking for. But luckily you do not need to use grep to find the right message. Here is example of what I had to do when I was looking for kernel messages.

journalctl _TRANSPORT=kernel
# To see all the fields, you can use the verbose mode
journalctl _TRANSPORT=kernel -o verbose

# And the filter on priority if needed to get the messages you need
journalctl _TRANSPORT=kernel PRIORITY=4

# and follow
journalctl _TRANSPORT=kernel PRIORITY=4 -f -l