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check open ports without netstat or lsof

Displays the current time using HTTP
This command will show the current GMT time using HTTP. This might be useful if you just want to know what's the current human-readable and accurate-enough time, without changing the system time, using a simple command that would work regardless of the availability of NTP. Note: To get a quicker and more accurate response, replace google.com with your local NTP server. Also can be used as an alternative to the "htpdate" program: http://www.commandlinefu.com/commands/view/668/set-your-computers-clock-using-http-and-htp-http-time-protocol-when-ntpsntp-is-not-available

Print all the lines between 10 and 20 of a file
Similarly, if you want to print from 10 to the end of line you can use: sed -n '10,$p' filename This is especially useful if you are dealing with a large file. Sometimes you just want to extract a sample without opening the entire file. Credit goes to wbx & robert at the comments section of http://www.commandlinefu.com/commands/view/348/get-line1000-from-text.#comment

Using scapy to get the IP of the iface used to contact local gw (i.e. supposed host IP)
You need python-scapy package

Find all files containing a word
shorter :p

Multiple SSH Tunnels
Thankfully, the ssh command allows you to specify multiple tunnels through the same server in one command. Remeber if you want a priviliged port on your machine, you must use root or sudo account.

Find the package that installed a command

Easy Persistent SSH Connections Using Screen
Use as: $ s host1 Will ssh to remote host upon first invocation. Then use C-a d to detatch. Running "s host1" again will resume the shell session on the remote host. Only useful in LAN environment. You'd want to start the screen on the remote host over a WAN. Adapted from Hack 34 in Linux Server Hacks 2nd Addition.

Show a curses based menu selector
Not so much handy by itself, but very nice in shell scripts. This makes you a handy ncurses based checklist. Much like terminal installers, just use the arrow keys and hit 'Space' to adjust the selections. Returns all selected tags as strings, with no newline at the end. So, your output will be something like: "one" "two" "three" "four" "etc" For those who prefer bash expansion over gratuitious typing: $ whiptail --checklist "Simple checkbox menu" 12 35 3 $(echo {one,two,three,four}" '' 0"} ) Things to note: The height must includes the outer border and padding: add 7 to however many items you want to show up at the same time. If the status is 1, it will be selected by default. anything else, will be deselected.

List all active access_logs for currently running Apache or Lighttpd process
Ever logged into a *nix box and needed to know which webserver is running and where all the current access_log files are? Run this one liner to find out. Works for Apache or Lighttpd as long as CustomLog name is somewhat standard. HINT: works great as input into for loop, like this: $ for i in `lsof -p $(netstat -ltpn|awk '$4 ~ /:80$/ {print substr($7,1,index($7,"/")-1)}')| awk '$9 ~ /access.log$/ {print $9| "sort -u"}'` ; do echo $i; done Very useful for triage on unfamiliar servers!


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