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Every new command is wrapped in a tweet and posted to Twitter. Following the stream is a great way of staying abreast of the latest commands. For the more discerning, there are Twitter accounts for commands that get a minimum of 3 and 10 votes - that way only the great commands get tweeted.
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Waits for all pings to complete and returns ip with mac address
find . -maxdepth 1 -iname ".*" | awk 'NR >= 2'
Can be used to list only dotfiles without . nor ..
GNU Awk 3.1.4
Btrfs reports the inode numbers of files with failed checksums. Use `find` to lookup the file names of those inodes. The files may need to be deleted and replaced with backups.
This command will use the fdisk utility to find all block devices on your system, and overwrite them with data from the /dev/urandom non-blocking random number generator.
CAUTION: This will irrevocably erase EVERY SINGLE physical block storage device visible to the fdisk utility, including plugged USB devices, RAID sets, LVM, etc.
List the busiest scripts/files running on a cPanel server with domain showing (column $12).
IP addresses and number of connections connected to port 80.
Easiest way to obtain the busiest website list (sorted by number of process running).
Choose the /var/log/sa/saXX log based on what day you want to view. You can use ifconfig to find the name of the interface.
You can use the -s flag to specify a certain time period, e.g. -s 12:00:00 -e 14:00:00
for redhat systems works sometimes :S tested on dell poweredge r7+ systems
show off how big your disks are
on some distro's you have to replace "BogoMIPS" with "bogomips".
Very quick! Based only on the content sizes and the character counts of filenames. If both numbers are equal then two (or more) directories seem to be most likely identical.
if in doubt apply:
diff -rq path_to_dir1 path_to_dir2
AWK function taken from here:
If you creates a virtualenv just for a test, and at the end, wants remove all installed packages. This is the lever.
Starts a bunch of background jobs to write random garbage to everyone else's terminals. The "\n" in IFS should be an actual newline, but I can't put that in the command.
recurse through all files, get the message hash, flip the output as filename, hash value
With this command, you can check the difference between the volumes mounted and the volume in /etc/fstab.
Using find's internal stat to get the file size is about 50 times faster than using -exec stat.