Commands by thelan (4)

What's this? is the place to record those command-line gems that you return to again and again. That way others can gain from your CLI wisdom and you from theirs too. All commands can be commented on, discussed and voted up or down.

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Move all comments the top of the file in vim
Python comments begin with a #. Modify to suit other languages. Other uses: Instead of m0 use m$ for end of file or d for deleting all comments.

Drop or block attackers IP with null routes
Someone might attack on your system. You can drop attacker IP using IPtables. However, you can use route command to null route unwanted traffic. A null route (also called as blackhole route) is a network route or kernel routing table entry that goes nowhere. Matching packets are dropped (ignored) rather than forwarded, acting as a kind of very limited firewall. The act of using null routes is often called blackhole filtering.

Monitor incoming connections of proxies and balancers.
Maybe this will help you to monitor your load balancers or reverse proxies if you happen to use them. This is useful to discover TIME OUTS and this will let you know if one or more of your application servers is not connected by checking.

Show a listing of open mailbox files (or whatever you want to modify it to show)

Update twitter with curl
Same as below, but no quotes are necessary when twitting more than one word

Apply an xdelta patch to a file
xdelta is a command line program for delta encoding, which generates the difference between two files. This is similar to diff and patch, but it is targeted for binary files and does not generate human readable output.

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

Undo commit in Mercurial

diff color words

Get the IP address of a machine. Just the IP, no junk.
Why use many different utilities all piped together, when you only need two?

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