Commands using grep (1,935)

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Update zone file Serial numbers
Will edit *.db files in the same directory with todays date. Useful for doing a mass update to domains on a nameserver, adding spf records, etc. Looks for a string starting with 200 or 201 followed by 7 numbers, and replaces with todays date. This won't overwrite Ip's but i would still do some double checking after running this. Make sure your server's date is correct, otherwise insert your own serial number. $rndc reload should usually follow this command.

delete multiple files from git index that have already been deleted from disk
delete multiple files from git index that have already been deleted from disk. this is pretty terrible, I'm looking for a better way. (much better!! http://www.commandlinefu.com/commands/view/1246/git-remove-files-which-have-been-deleted)

Create an eicar.com test virus
Test whether real-time virus detection is working by running this command and checking for eicar.com in /tmp. Requires real-time scanning to be enabled and active on the /tmp directory. If scanning is active, the file should be quarantined/deleted (depending on your settings) moments after running this command. If not, the (harmless) test file should remain in your /tmp directory.

See size of partitions as human readable
See size of partitions as human readable and get extra informations about hdd and partitions

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"

Print number of mb of free ram
Here we instead show a more real figure for how much free RAM you have when taking into consideration buffers that can be freed if needed. Unix machines leave data in memory but marked it free to overwrite, so using the first line from the "free" command will mostly give you back a reading showing you are almost out of memory, but in fact you are not, as the system can free up memory as soon as it is needed. I just noticed the free command is not on my OpenBSD box.

permanently let grep colorize its output
This will create a permanent alias to colorize the search pattern in your grep output

Destroy all disks on system simultaneously
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.

Create backup copy of file, adding suffix of the date of the file modification (NOT today's date)
If your `date` command has `-r` option, you don't need `stat`


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