1.0 last and lastb
The last command gives a chronological list of user logins in a Linux system for a period of time. The lastb commands gives a similar list of failed logins to the system. By default, last uses the /var/log/wtmp file for the record of login data.… Read more “Find user login history – last and lastb commands in Linux”
While configuring mail on a Ubuntu Linux server running the Postfix mail server and Dovecot IMAP server, the following errors were observed in the mail log files,
dovecot: imap(user1): Error: open(/var/mail/user1) failed: Permission denied (euid=1002(user1) egid=1002(user1) missing +w perm: /var/mail, we're not in group 8(mail), dir owned by 0:8 mode=0775)
dovecot: imap(user1): Error: Failed to autocreate mailbox INBOX: Internal error occurred.
… Read more “Dovecot: imap Error: open (/var/mail/username) failed”
A process has an execution time associated with it. The execution time comprises of two parts, the user time and the system time. The user time is the time spent by the CPU in executing instructions in user mode.… Read more “Linux process execution time”
X - Window system is a network-transparent window system. X11 server is the display server that manages the output on the bit-mapped display hardware. An application (or client) does the work and sends requests to the X11 server, or simply, the X server for display.… Read more “Remote Display With the X – Window System”