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check open ports without netstat or lsof

Generate binary sequence data

Show crontabs for all users
added echo "### Crontabs for $user ####"; to make clear whose crontab is listed.

FizzBuzz in one line of Bash
The (in)famous "FizzBuzz" programming challenge, answered in a single line of Bash code. The "|column" part at the end merely formats the output a bit, so if "column" is not installed on your machine you can simply omit that part. Without "|column", the solution only uses 75 characters. The version below is expanded to multiple lines, with comments added. for i in {1..100} # Use i to loop from "1" to "100", inclusive. do ((i % 3)) && # If i is not divisible by 3... x= || # ...blank out x (yes, "x= " does that). Otherwise,... x=Fizz # ...set x to the string "Fizz". ((i % 5)) || # If i is not divisible by 5, skip (there's no "&&")... x+=Buzz # ...Otherwise, append (not set) the string "Buzz" to x. echo ${x:-$i} # Print x unless it is blanked out. Otherwise, print i. done | column # Wrap output into columns (not part of the test).

create ext4 filesystem with big count of inodes
XX is your device partition number like /dev/sdc1 . to see how many inodes your partition have type: $ df --inodes (or df -i) Default formatting with ext4 would create small inode count for the new partition if you need big count of inodes is the fstype news the correct one. in debian you can see which fstype exists as template in: $ vim /etc/mke2fs.conf if you format default ext for a partition size with 1TB you would get 1 Million inodes (not enough for backupStorages) but if you format with fstype news you would get hunderd of millions of inodes for the partition. you have tune $/etc/sysctl.conf also with following sysconfig parameters $ fs.file-max = XXX $ fs.nr_open = XXX where XXX is the count of max inodes for whole system

Find the package that installed a command

Set blanket packet/second limit on network interface for Ubuntu VPS server
VPS server hosts suspect DOS attack if PPS is too high. This limits packets at the interface level. Do "sudo apt-get install iptables-persistent" to make persistent, or, if you already have, reconfigure with "sudo dpkg-reconfigure iptables-persistent"

Bash alias for creating screen session containing IRSSI, named irssi, while checking if existing session is created
Bash alias for easy irssi within screen, attempts to attach to existing irssi session, if one exists, otherwise creates one - Including wipe for when system reboots and leaves "dead" session.

Mount/unmount your truecrypted file containers
This should automatically mount it to /media/truecrypt1. Further mounts will go to /media/truecrypt2, and so on. You shouldn't need sudo/su if your permissions are right. I alias tru='truecrypt' since tr and true are commands. To explicitly create a mount point do: tru volume.tc /media/foo To make sure an GUI explorer window (nautilus, et al) opens on the mounted volume, add: --explorer To see what you currently have mounted do: tru -l To dismount a volume do: tru -d volume.tc. To dismount all mounted volumes at once do: tru -d Tested with Truecrypt v6.3a / Ubuntu 9.10

Export all Mailman mailing lists Members to separate .txt files
Export all Mailman mailing lists Members to separate .txt files excluding "Mailman" and "Test" or add yours by && $1!="myDontWannaList"


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