The Random Information Post

This is a sort of catch-all post that will house random coding/sysadmin things I don’t use enough to memorize.

Network Drives

Mount a volume over SSH

sshfs -p 2345 -o IdentityFile=~/.ssh/id_rsa user@domain.com:/remote/path /target/path

SQL

Compress a mysqldump

mysqldump -u user -p -B database_name | gzip > ~/backups/backup1.gz;

Video

Merging AVI files

mencoder -noskip -oac copy -ovc copy `ls 20150203*avi` -o digest.avi

add -mc for audio sync

Renaming files using regular expressions

I had a bunch of backed up files with names like:

* 201506.pdf_2015_10_08_160622
* 201507.pdf_2015_10_08_160622

To remove the timestamp suffix, I used the rename utility. I had to install it with homebrew in Mac OS, but it works great:

rename 's/_2015_[0-9]{2}_[0-9]{2}_[0-9]{6}//' 2015*

ran in the above directory will give files named

* 201506.pdf
* 201507.pdf

Securely Wipe Drive

dd if=/dev/zero of=/dev/sdX iflag=nocache oflag=direct bs=4096

Convert all mkv files to mp4 in folder

for f in *.mkv; do avconv -i "$f" -codec copy "${f%.mkv}.mp4"; done