Commands by wei2912 (2)

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Connect via sftp to a specific port
I use this for connect via sftp to a server listening on a non default ssh port.

Netcat brute force on administration login panel

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

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

Change every instance of OLD to NEW in file FILE
Very quick way to change a word in a file. I use it all the time to change variable names in my PHP scripts (sed -i 's/$oldvar/$newvar/g' index.php)

Detect illegal access to kernel space, potentially useful for Meltdown detection
Based on capsule8 agent examples, not rigorously tested

Make a server's console beep when the network is down
This is like ping -a, but it does the opposite. It alerts you if the network is down, not up. Note that the beep will be from the speaker on the server, not from your terminal. Once a second, this script checks if the Internet is accessible and beeps if it is not. I define the Net as being "UP", if I can ping Google's public DNS server (8.8.8.8), but of course you could pick a different static IP address. I redirect the beep to /dev/console so that I can run this in the background from /etc/rc.local. Of course, doing that requires that the script is run by a UID or GID that has write permissions to /dev/console (usually only root). Question: I am not sure if the -W1 flag works under BSD. I have only tested this under GNU/Linux using ping from iputils. If anybody knows how portable -W is, please post a comment.

Force machine to reboot no matter what (even if /sbin/shutdown is hanging)
This will cause your machine to INSTANTLY reboot. No un-mounting of drives or anything. Very handy when something has gone horribly wrong with your server in that co-location facility miles away with no remote hands! Suspect this works with all 2.2, 2.4 and 2.6 Linux kernels compiled with magic-syskey-request support.

Fetch all GPG keys that are currently missing in your keyring
For instance, if people have signed your key, this will fetch the signers' keys.

List files older than one year, exluding those in the .snapshot directory
Useful when you want to cron a daily deletion task in order to keep files not older than one year. The command excludes .snapshot directory to prevent backup deletion. One can append -delete to this command to delete the files : $ find /path/to/directory -not \( -name .snapshot -prune \) -type f -mtime +365 -delete


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