Sort a list of IPV4 addresses in numerical order. Great as a filter, or within vim using !} Show Sample Output
Here is a command line to run on your server if you think your server is under attack. It prints our a list of open connections to your server and sorts them by amount.
BSD Version:
netstat -na |awk '{print $5}' |cut -d "." -f1,2,3,4 |sort |uniq -c |sort -nr
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This can be much faster than downloading one or both trees to a common servers and comparing the files there. After, only those files could be copied down for deeper comparison if needed. Show Sample Output
Plot your most used commands with gnuplot.
In this case I'm just grabbing the next level of subdirectories (and same level regular files) with the --max-depth=1 flag. leaving out that flag will just give you finer resolution. Note that you have to use the -h switch with both 'du' and with 'sort.' Show Sample Output
i'm using gawk, you may get varying mileage with other varieties. You might want to change the / after du to say, /home/ or /var or something, otherwise this command might take quite some time to complete. Sorry it's so obsfucated, I had to turn a script into a one-liner under 255 characters for commandlinefu. Note: the bar ratio is relative, so the highest ratio of the total disk, "anchors" the rest of the graph. EDIT: the math was slightly wrong, fixed it. Also, made it compliant with older versions of df. Show Sample Output
usefull in case of abuser/DoS attacks. Show Sample Output
A more efficient way, with reversed order to put the focus in the big ones. Show Sample Output
Very useful when you need disk space. It calculates the disk usage of all files and dirs (descending them) located at the current directory (including hidden ones). Then sort puts them in order.
using
cat WAR_AND_PEACE_By_LeoTolstoi.txt | tr -cs "[:alnum:]" "\n"| tr "[:lower:]" "[:upper:]" | sort -S16M | uniq -c |sort -nr | cat -n | head -n 30
("sort -S1G" - Linux/GNU sort only) will also do the job but as some drawbacks (caused by space/time complexity of sorting) for bigger files...
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... plus do a sort according frequency Show Sample Output
Search for files and list the 20 largest.
find . -type f
gives us a list of file, recursively, starting from here (.)
-print0 | xargs -0 du -h
separate the names of files with NULL characters, so we're not confused by spaces
then xargs run the du command to find their size (in human-readable form -- 64M not 64123456)
| sort -hr
use sort to arrange the list in size order. sort -h knows that 1M is bigger than 9K
| head -20
finally only select the top twenty out of the list
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This command will find the biggest files recursively under a certain directory, no matter if they are too many. If you try the regular commands ("find -type f -exec ls -laSr {} +" or "find -type f -print0 | xargs -0 ls -laSr") the sorting won't be correct because of command line arguments limit. This command won't use command line arguments to sort the files and will display the sorted list correctly. Show Sample Output
sorts the contents of a file without the need for a second file to take the sorted output. This was previously entered as `sort -g list.txt -o $_` but as others have pointed out the $_ references the previous command. so this would've worked had that been the second part of a command joined with && like: cat list.txt && sort -g list.txt -o $_ The user below me Robin had the most correct command. Show Sample Output
This command checks for the number of times when someone has tried to login to your server and failed. If there are a lot, then that user is being targeted on your system and you might want to make sure that user either has remote logins disabled, or has a strong password, or both. If your output has an "invalid" line, it is a summary of all logins from users that don't exist on your system. Show Sample Output
find -printf '%u\n' | sort | uniq #just users find -printf '%g\n' | sort | uniq #just groups Show Sample Output
Searches the /var/log/secure log file for Failed and/or invalid user log in attempts. Show Sample Output
Each shell function has its own summary line, as a comment. If there are multiple shell functions with the same name, the function with the highest number of votes is put into the file. Note: added 'grep -v' to the end of the pipeline, to eliminate extraneous lines containing only '--'. Thanks to matthewbauer for pointing this out.
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