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See a full last history by expanding logrotated wtmp files
When your wtmp files are being logrotated, here's an easy way to unpack them all on the fly to see more than a week in the past. The rm is the primitive way to prevent symlink prediction attack.

Use a var with more text only if it exists
See "Parameter Expansion" in the bash manpage. They refer to this as "Use Alternate Value", but we're including the var in the at alternative.

Show your account and windows policy settings with Results of Policy msc.
Type this into windows via run and it will display to you your complete policy for windows. This includes group policy, security policy and your active directory account (min password etc).... www.fir3net.com

Create a tar of directory structure only

Print current runlevel
Prints current runlevel and system start time. On older systems it also shows the last init state. Pretty useful on remote systems, pretty useless on local ones :)

Extract busiest times from apache access log
Analyze an Apache access log for the time period with most activity and display the hit count, requesting IP and the timestamp. May help detect a brute force dos attack.

checks size of directory & delete it if its to small
only simple example how to combine rclone & jq

Running scripts after a reboot for non-root users .
Sometimes we may want to run a script when a system reboots . We can simply do this by just scheduling the script using vixie cron with the @reboot option . e.g @reboot I use it to send me an alert message on our prod hosts to send an alert message when the system reboots . @reboot zaman uptime | echo `uptime` | mail -s "`uname -n` got rebooted" me@myhost.com

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

Remove all .svn folders
-depth argument will cause find to do a "depth first" tree search, this will eliminate the "No such file or directory" error messages


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