Linux Ask! is a Q & A web site specific for Linux related questions. Questions are collected, answered and audited by experienced Linux users.
How to install bulk packages using yum with groupinstall?
Answer:
Sometimes, if you forgot to select "Development Tools" during Fedora/CentOS installations, you can add them later by using one command
yum groupinstall "Development Tools"
Which save you a lot of times from installing the needed packages one by one.
To see what options are available for groupinstall, try
yum grouplist
How to zip a file in Ubuntu?
Answer:
Firstly, install the "zip" package if not installed
sudo apt-get install zip
Then run the command
zip test.zip test.txt
How to mount a NFS share?
Answer:
Assume you have a NFS share /data/shares/music, at server: 192.168.1.5
You can mount the NFS share from another system at /mnt/music (create this directory first), with the command below
sudo mount 192.168.1.5:/data/shares/music /mnt/music
This is just an one-time mount.
If you want to mount permanently, you can edit the fstab
vi /etc/fstab
and input
192.168.1.5:/data/shares/music /mnt/music nfs rsize=8192,wsize=8192,timeo=14,intr
Then run the command to see the effect immediately.
sudo mount /mnt/music
Also try to reboot your system to see if the share can be mounted automatically or not.
How to perform checksum on a file?
Answer:
You can use the md5sum or shasum commands.
Example
#md5sum test.txt
f1d41356dcabb8d8acefed069b22b0da test.txt
#shasum test.txt
809970aec0109c5464dd36a3a9a5a9e79f838313 test.txt
md5sum is faster if you perform the command on a very large file, but shasum is more secure since the chance of two different files have the same checksum is smaller.
References:
How to print out a newline character using the echo command?
Answer:
If you try
echo "foo\nbar"
It will print out
foo\nbar
But if you want the two words separate by an actual newline, you can use
echo -e "foo\nbar"
Output would be
foo
bar
You can combine the "-e" flag with other control characters such as "\t", "\r", "\v"... as well.
