[COFF] Useful Shell Scripts Network Connections , Logins and Block hacking attempts

[Ralph Corderoy]

Hi,

>From a quick skim, these seem poorly written.  They might do what's
required some of the time but are no better than a quickly knocked-up
attempt I'd do myself.

> Use the awk command to display only the data in column 5, and then
> display the information of the IP address in column 1
...
> netstat -atn  |  awk  '{print $5}'  | awk  '{print $1}' | sort -nr  |  uniq -c

The second awk does nothing, even though it's documented.

> find $dir -type f|xargs md5sum > /tmp/md5_a.txt
> ssh $b_ip "find $dir -type f|xargs md5sum > /tmp/md5_b.txt"
> scp $b_ip:/tmp/md5_b.txt /tmp
> #Compare file names as traversal objects one by one
> for f in `awk '{print 2} /tmp/md5_a.txt'`

Looks like that ‘print 2’ should be $2.  Presumably it was corrupted on
its long journey of cut-and-pastes and renderings.  The '' quoting is
also adrift as what's there lumps the AWK with the input's path.

> if grep -qw "$f" /tmp/md5_b.txt

This checks if an A file is present in B.  There is nothing to spot new
files in B not in A.

> then
> md5_a=`grep -w "$f" /tmp/md5_a.txt|awk '{print 1}'`
> md5_b=`grep -w "$f" /tmp/md5_b.txt|awk '{print 1}'`

Both 1 should be $1 to get the MD5 for the path.  And grep's -w isn't
the right way to pick out the line.

    $ md5sum * | grep -w foo
    d41d8cd98f00b204e9800998ecf8427e  foo
    d41d8cd98f00b204e9800998ecf8427e  foo extra
    $

I didn't read further.

-- 
Cheers, Ralph.