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Displays user-defined ps output and pidstat output about the top CPU or MEMory users.
It grabs the PID's top resource users with $(ps -eo pid,pmem,pcpu| sort -k 3 -r|grep -v PID|head -10) The sort -k is sorting by the third field which would be CPU. Change this to 2 and it will sort accordingly. The rest of the command is just using diff to display the output of 2 commands side-by-side (-y flag) I chose some good ones for ps. pidstat comes with the sysstat package(sar, mpstat, iostat, pidstat) so if you don't have it, you should. I might should take off the timestamp... :|

Figure out what shell you're running
short, sweet, and works after sudoing a new shell.

Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

See why a program can't seem to access a file
Sometimes a program refuses to read a file and you're not sure why. You may have display_errors turned off for PHP or something. In this example, fopen('/var/www/test/foo.txt') was called but doesn't have read access to foo.txt. Strace can tell you what went wrong. E.g., if php doesn't have read access to the file, strace will say "EACCESS (Permission denied)". Or, if the file path you gave doesn't exist, strace will say "ENOENT (No such file or directory)", etc. This works for any program you can run from the command-line, e.g., strace python myapp.py -e open,access... Note: the above command uses php-cli, not mod_php, which is a different SAPI with diff configs, etc.

Run netcat to server files of current folder

LDAP search to query an ActiveDirectory server
These are the parameters to ldapsearch (from ldap-utils in Ubuntu), for searching for the record for Joe Blogg's user. sAMAccountName is the LDAP field that ActiveDirectory uses to store the user name. 'DOMAIN\Joe.Bloggs' where "DOMAIN" is the the active directory domain. Othewise you could use "CN=Joe.Bloggs,DC=example,DC=com" instead of "DOMAIN\Joe.Bloggs"

Rename files in batch

Update dyndns.org with your external IP.
This is great if you are behind a router that does not support dynamic dns updates! Example: AT&T u-verse gateway... Put this in a script and run it as a cron job.

copy partition table from /dev/sda to /dev/sdb

show current directory
Opens a file or URL in the user's preferred application.


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