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Let's not forget awk!
Like i said, i havent test it yet, all becouse my internet its soo slow, if you try and works please share, also be nice to do it using the direct url link.
#_connects src_IP dst_IP When_It_Happened_Secs
`mount -o remount` doesn't pick up new NFS options (eg. timeo, soft, retrans, etc) so you need to do a full mount/remount cycle. This one-liner makes it quick and easy :) Update your fstab with the new options, then run it.
Using the output of 'ps' to determine CPU usage is misleading, as the CPU column in 'ps' shows CPU usage per process over the entire lifetime of the process. In order to get *current* CPU usage (without scraping a top screen) you need to pull some numbers from /proc/stat. Here, we take two readings, once second apart, determine how much IDLE time was spent across all CPUs, divide by the number of CPUs, and then subtract from 100 to get non-idle time.
Searches for *.cpp and *.h in directory structure, counts the number of lines for each matching file and adds the counts together.
`multipath -ll` requires Device Mapper multipath.conf configuration. And of course, replace "3PARdata,VV" with your disk array's SCSI vendor,LUN name.
- GPT partition table allows you to create >2TB partitions
The lastb command presents you with the history of failed login attempts (stored in /var/log/btmp). The reference file is read/write by root only by default. This can be quite an exhaustive list with lots of bots hammering away at your machine. Sometimes it is more important to see the scale of things, or in this case the volume of failed logins tied to each source IP.
The awk statement determines if the 3rd element is an IP address, and if so increments the running count of failed login attempts associated with it. When done it prints the IP and count.
The sort statement sorts numerically (-n) by column 3 (-k 3), so you can see the most aggressive sources of login attempts. Note that the ':' character is the 2nd column, and that the -n and -k can be combined to -nk.
Please be aware that the btmp file will contain every instance of a failed login unless explicitly rolled over. It should be safe to delete/archive this file after you've processed it.
This will take the packages matching a given `apt-cache search` query (a collection of AND'd words or regexps) and tell you how popular they are. This is particularly nice for those times you have to figure out which solution to use for e.g. a PDF reader or a VNC client.
Substitute "ubuntu.com" for "debian.org" if you want this to use Ubuntu's data instead. Everything else will work perfectly.
Get the current cpu % usage on your system.
Uses the --porcelain option, which is garanteed to be stable among git versions and configurations - also, is way easier to parse.
I came up with this because I don't have a problem remembering the big major changes I made deep inside my tree for a specific feature or bugfix but always manage to forget the trivial stuff I tweaked or touched along the way that needs to get pushed as well.
The command will make it easy to determine free IP ranges in a crowded sub-net.