Commands by HaoZeke (3)

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Migrate existing Ext3 filesystems to Ext4
Before doing this, back-up all data on any ext3 partitions that are to be converted to ext4. After running previous command you MUST run fsck, is needed to return the filesystem to a consistent state. $ fsck -pDf /dev/yourpartition Edit /etc/fstab and change the 'type' from ext3 to ext4 for any partitions that are converted to ext4.

Look at your data as a greymap image.
Keep width to a power of 2 to see patterns emerge. 512 is good. So is 4096 for huge maps. PNM headers are super basic. http://netpbm.sourceforge.net/doc/pbm.html

Display total Kb/Mb/Gb of a folder and each file

Diff files over SSH
Sometimes you need to compare two config files on different servers. Put the file names into the above script and let 'er rip.

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

Get the serial numbers from HP RAID
This dumps serial numbers of all the drives but HP warranty check does not say they are valid ...

Remotely sniff traffic and pass to snort
I have a small embedded linux device that I wanted to use for sniffing my external network, but I didn't want to recompile/cross-compile snort for the embedded platform. So I used tcpdump over ssh to pass all the traffic as pcap data to a "normal" Linux system that then takes the pcap data and passes it to snort for processing.

Force an fsck on reboot
Force an fsck on reboot. Useful on a system where / has mounted read-only because of file system issues.

Get International Space Station sighting information for your city
This command outputs a table of sighting opportunities for the International Space Station. Find the URL for your city here: http://spaceflight.nasa.gov/realdata/sightings/

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"


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