linux

Motivation When I migrate Amazon Linux to Amazon Linux2, I investigate how to change file descriptor limits and number of process per user on Linux server working with systemd. This post is technical memo for myself. I try the following procedure after booting the official Amazon Linux 2 AMI as it is. Soft limits and Hard limits Let me review what Soft limits and Hard limits are. Linux limits the number of process per user.

Motivation When I migrate Amazon Linux to Amazon Linux2, I investigate how to change system clock on Linux server working with systemd. This post is technical memo for myself. Change system clock System clock is calculated by /etc/adjtime that uses hardware clock. If OS working with systemd dosen’t have /etc/adjtime, UTC is default. cat /etc/adjtime > 0.0 0 0.0 > 0 > UTC Now check the system clock with timedatectl command.