Commands by pluc (2)

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convert strings toupper/tolower with tr

a function to find the fastest DNS server
http://public-dns.info gives a list of online dns servers. you need to change the country in url (br in this url) with your country code. this command need some time to ping all IP in list.

Read all the S.M.A.R.T. data from a hard disk drive
This is to pull all the saved S.M.A.R.T. (Self-Monitoring, Analysis and Reporting Technology) information from a hard drive. This can give you an idea of the nature and extent of an issue on a failing hard drive.

Print a list of installed Perl modules
This version works on an AIX system on which I have very limited permissions. The other version fails with "Can't open file /usr/opt/perl588/lib/site_perl/5.8.8/aix/auto/DBI/.packlist".

Perform a branching conditional
This will perform one of two blocks of code, depending on the condition of the first. Essentially is a bash terniary operator. To tell if a machine is up: $ ping -c1 machine { echo succes;} || { echo failed; } Because of the bash { } block operators, you can have multiple commands $ ping -c1 machine && { echo success;log-timestamp.sh }|| { echo failed; email-admin.sh; } Tips: Remember, the { } operators are treated by bash as a reserved word: as such, they need a space on either side. If you have a command that can fail at the end of the true block, consider ending said block with 'false' to prevent accidental execution

Capture all plaintext passwords

start vim in diff mode
vim will open both files side by side and show colored diffs

Simple Video Surveillance by email
This takes a picture (with the web cam) every 5 minutes, and send the picture to your e-mail. Some systems support mail -a "References: " so that all video surveillance emails are grouped in a single email thread. To keep your inbox clean, it is still possible to filter and move to trash video surveillance emails (and restore these emails only if you really get robbed!) For instance with Gmail, emails sent to me+trash@gmail.com can be filtered with "Matches: DeliveredTo:me+trash@gmail.com"

Find the package that installed a command

Intercept, monitor and manipulate a TCP connection.
Forwards localhost:1234 to machine:port, running all data through your chain of piped commands. The above command logs inbound and outbound traffic to two files. Tip: replace tee with sed to manipulate the data in real time (use "sed -e 's/400 Bad Request/200 OK/'" to tweak a web server's responses ;-) Limitless possibilities.

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