Extending LVM logical volume when 100% utilized

 When the logical volume is 100% used and you try to extend the logical volume, you will likely encounter the following error. 

# lvextend -L+5G /dev/mapper/vgname_lvname
 Couldn't create temporary archive name.
 Volume group "vgname" metadata archive failed.

A quick way to extend even when the volume is 100% utilize is by disabling autobackup (using -An)

# lvextend -An -L+5G /dev/mapper/vgname_lvname

Until next time!!!

sed Search and Replace with forward slash "/"

I always enjoy performing search and replace using sed command when I need to edit the same thing over multiple files. Usually the syntax that I use is as follow:

sed -i 's/search/replacement/' *.txt

This will replace all the word "search" with "replacement" in all files that ended with txt. 

But what if you want to replace the word "search" with "replace/ment". You just need to do minor adjustment as follow:

sed -i "s|search|replace/ment|" *.txt

Usually I omit the "-i" first to see the changes on the screen to make sure that the text are replaced properly before adding "-i" to perform the actual changes. 

Until next time!!! 

SSH Tunneling - Simple localhost port forwarding

 Recently I saw an application that run on 127.0.0.1 port 8080 on the server that I need to access from my workstation. The easiest way to access this is to use ssh tunneling. 

To tunnel remote port to local machine, you can just perform the following:

ssh -g -L 9999:localhost:8080 -f -N username@remoteip

This will allow your local machine port 9999 to be tunneled to the remote machine application on port 8080

Launch your browser and login to http://localhost:9999 and you will be accessing the application running on the server localhost.   

Until next time :)