Commands by Wallebot (5)

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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

Check availability of Websites based on HTTP_CODE

Output system statistics every 5 seconds with timestamp
See man vmstat for information about the statistics. This does the same thing without the timestamp: $vmstat 5

Create a new file

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"

Arch Linux sort installed packages by size
This one-liner will output installed packages sorted by size in Kilobytes.

show all programs connected or listening on a network port
Use the aliased command 'nsl'

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

Get the date for the last Saturday of a given month
If your locale has Monday as the first day of the week, like mine in the UK, change the two $7 into $6

Convert CSV to JSON with miller
Using the csv tool `miller` you can transform a csv file into a json array of objects, where the properties are the values of the csv header line and the values are the values of the subsequent lines.


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