Commands tagged shell (92)

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Remove a line in a text file. Useful to fix "ssh host key change" warnings

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Edit all files found having a specific string found by grep
The grep switches eliminate the need for awk and sed. Modifying vim with -p will show all files in separate tabs, -o in separate vim windows. Just wish it didn't hose my terminal once I exit vim!!

Remove blank lines from a file using grep and save output to new file
The ^$ within the quotes is a regular expression: ^=beginning of line, $=end of line, with no characters between.

see the TIME_WAIT and ESTABLISHED nums of the network
see the TIME_WAIT and ESTABLISHED nums of the network

Watch your freebox flux, through a other internet connection (for French users)
You can watch channels of your freebox, everywhere. With " vlc http://your-ip:12345 " on the client and ncurses vlc interface on the host. et voila

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Port scan a range of hosts with Netcat.
Simple one-liner for scanning a range of hosts, you can also scan a range of ports with Netcat by ex.: nc -v -n -z -w 1 192.168.0.1 21-443 Useful when Nmap is not available:) Range declaration like X..X "for i in {21..29}" is only works with bash 3.0+

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

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"


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