Things on this page are fragmentary and immature notes/thoughts of the author. Please read with your own judgement!

Tips and Traps

1. The command rsync -avh src_dir des_dir (src_dir has no trailing slash) synchronizes the whole directory src_dir into the destination directory des_dir while rsync -avh src_dir/ des_dir (src_dir/ has …

Things on this page are fragmentary and immature notes/thoughts of the author. Please read with your own judgement!

From Linux to Linux

Command Line Mode Using ssh

1. Using X forwarding, you can also run GUI applications on the server. This is not recommended unless it's short quick work.

Remote …

Things on this page are fragmentary and immature notes/thoughts of the author. Please read with your own judgement!

The best way to "recover deleted files" is really to avoid permanently delete files. It is suggested that you avoid using the rm command (unless you are 100% sure what you …

Things on this page are fragmentary and immature notes/thoughts of the author. Please read with your own judgement!

Tricks and Traps

1. Use full paths of commands when you use a batch account or schedule a cron job. The reason is that batch account and/or cron might have different …

Things on this page are fragmentary and immature notes/thoughts of the author. Please read with your own judgement!

Note: You might have to do this every time you upgrade your Linux kernel!!

Symptoms

Below are step-by-step symptoms from superficial to root causes.

1. Your Linux system becomes very slow even …

Things on this page are fragmentary and immature notes/thoughts of the author. Please read with your own judgement!

1. List all services names.

   service --status-all
   

2. List all systemd units.

   systemctl
   

3. Disable a service.

   systemctl disable service_name
   

4. Check whether systemd is running as PID 1.

   ps --no-headers -o comm 1
   

A …