Reverse characters on each line
Answer:
To reverse characters on each line, e.g.
abc
def
Become...
cba
fed
You can use the rev command:
# rev input.txt
Feb 202010
Feb 162010
Mount a filesystem by UUID in Linux
Anwser:
Assumed you know the UUID of your harddisks, you want to mount it for use, try the following method:
# mount -U 9f95f559-9986-4dfc-8661-849bb54ed5a5 /mnt/data1Feb 162010
How to list all the UUID of my hard disks
Answer:
To list all the UUID of my hard disks, you can use the blkid command.
# sudo blkid
/dev/sda1: UUID="9f95f559-9986-4dfc-8661-849bb54ed5a5" TYPE="ext3"
/dev/sda5: TYPE="swap" UUID="0fe4eedc-65dd-4b46-85c9-11795f2cdc57"
Feb 132010
How to shutdown a frozen Linux System?
Answer:
Similar to this post, but this time you are going to shutdown a frozen Linux system.
- Hold down the Alt and SysRq (Print Screen) keys
- While holding those down, type the following in order: REISUO
- You computer will shutdown now
The last letter O tell the system to shutdown. Replace by the letter R if you want reboot instead.
Feb 122010
Immediate time synchronization in RHEL/CentOS/Fedora
Answer:
If you want to sync the system time without installing ntpd package, rdate is an older way but it will do what you need.
# rdate -s ntp0.cornell.eduYou can find a list of time servers at: http://pank.org/blog/2004/08/time-server-list.html
