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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.
Count on a specific port (80) - FreeBSD friendly.
Now we can capture only a specific window (we have to chose by clicking on it)
ffmpeg complains about "Frame size must be a multiple of 2" so we calculate the upper even number with (g)awk trickery.
We remove the grep, we are already using (g)awk here ....why losing time with grep !!! ;)
Remove old kernels (*-generic and *-generic-pae) via apt-get on debian/ubuntu based systems. Tested on ubuntu 10.04 - 12.04.
Use this the next time you need to come up with a reasonably random bitstring, like for a WPA/WPA2 PSK or something. Takes a continuous stream of bytes coming from /dev/urandom, runs it through od(1), picking a random field ($0 and $1 excluded) from a random line and then prints it.
Depending on your Apache access log configuration you may have to change the sum+=$11 to previous or next awk token.
Beware, usually in access log last token is time of response in microseconds, penultimate token is size of response in bytes. You may use this command line to calculate sum and average of responses sizes.
You can also refine the egrep regexp to match specific HTTP requests.
That's the easiest way to do it. -I (or capital i) display all network addresses of a host
gives u each configured IP in a seperate line.
cut -f1,2 - IP range 16
cut -f1,2,3 - IP range 24
cut -f1,2,3,4 - IP range 24
This command allows you to revert every modified file one-by-one in a while loop, but also after "echo $file;" you can do any sort of processing you might want to add before the revert happens.
Will split the std input lines into files grouped by the 5th column content.
If your locale has Monday as the first day of the week, like mine in the UK, change the two $7 into $6
This was done in csh.
This is a little trickier than finding the last Sunday, because you know the last Sunday is in the first position of the last line. The trick is to use the NF less than or equal to 7 so it picks up all the lines then grep out any empty lines.
Simpler and without all of the coloring gimmicks. This just returns a list of branches with the most recent first. This should be useful for cleaning your remotes.
small update for this command to work with linux kernels 3.x
Like the original version except it does not include the parent apache process or the grep process and adds "sudo" so it can be run by user.
Prints top 5 twitter topics. Not very well written at all but none of the others worked.
Improvement on Coderjoe's Solution. Gets rid of grep and cut (and implements them in awk) and specifies some different mplayer options that speed things up a bit.
This will save parsing time for operations on very big files.
Convert readable date/time with `date` command