Commands using uniq (255)

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find files containing text
I find this format easier to read if your going through lots of files. This way you can open the file in any editor and easily review the file

Use tagged vlans
Great for sysadmins! Don't forget to pass the vlan to your port in a manageable switch. After vconfig, you should use $sudo ifconfig eth0.[VID] up Now the interface is up, you can use dhclient or ifconfig again to get an ip address.

check open ports (both ipv4 and ipv6)
While `lsof` will work, why not use the tool designed explicitly for this job? (If not run as root, you will only see the names of PID you own)

Erase empty files
The command find search commands with size zero and erase them.

1+2-3+4-5+6-7 Series

Reduce PDF size

Block known dirty hosts from reaching your machine
Blacklisted is a compiled list of all known dirty hosts (botnets, spammers, bruteforcers, etc.) which is updated on an hourly basis. This command will get the list and create the rules for you, if you want them automatically blocked, append |sh to the end of the command line. It's a more practical solution to block all and allow in specifics however, there are many who don't or can't do this which is where this script will come in handy. For those using ipfw, a quick fix would be {print "add deny ip from "$1" to any}. Posted in the sample output are the top two entries. Be advised the blacklisted file itself filters out RFC1918 addresses (10.x.x.x, 172.16-31.x.x, 192.168.x.x) however, it is advisable you check/parse the list before you implement the rules

ls -hog --> a more compact ls -l
I often deal with long file names and the 'ls -l' command leaves very little room for file names. An alternative is to use the -h -o and -g flags (or together, -hog). * The -h flag produces human-readable file size (e.g. 91K instead of 92728) * The -o suppresses the owner column * The -g suppresses the group column Since I use to alias ll='ls -l', I now do alias ll='ls -hog'

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

resolving basic authentication problem(401) with wget
I have a server with a php requiring basic authentication, like this:


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