November 2008
Linux.com :: Parallel SSH execution and a single shell to control them all
by camel (via)Many people use SSH to log in to remote machines, copy files around, and perform general system administration. If you want to increase your productivity with SSH, you can try a tool that lets you run commands on more than one remote machine at the same time. Parallel ssh, Cluster SSH, and ClusterIt let you specify commands in a single terminal window and send them to a collection of remote machines where they can be executed.
Why you would need a utility like this when, using openSSH, you can create a file containing your commands and use a bash for loop to run it on a list of remote hosts, one at a time? One advantage of a parallel SSH utility is that commands can be run on several hosts at the same time. For a short-running task this might not matter much, but if a task needs an hour to complete and you need to run it on 20 hosts, parallel execution beats serial by a mile. Also, if you want to interactively edit the same file on multiple machines, it might be quicker to use a parallel SSH utility and edit the file on all nodes with vi rather than concoct a script to do the same edit.
Many of these parallel SSH tools include support for copying to many hosts at once (a parallel version of scp) or using rsync on a collection of hosts at once. Because the parallel SSH implementations know about all the hosts in a group, some of them also offer the ability to execute a command "on one host" and will work out which host to pick using load balancing. Finally, some parallel SSH projects let you use barriers so that you can execute a collection of commands and explicitly have each node in the group wait until all the nodes have completed a stage before moving on to the next stage of processing.
August 2008
IE WebDeveloper - DOM Inspector, Script Console, Logging messages and HTTP Monitor
by camelIE WebDeveloper is an add-on for Microsoft Internet Explorer. The rich web debugging toolset allows you to inspect and edit the live HTML DOM and current cascaded styles, evaluate expressions and display error messages, log messages, explore source code of webpage and monitor DHTML Event and HTTP Traffic.
July 2008
April 2008
Logmonster FAQ - The Network People, Inc.
by camelTypical Scenario: You have a web server that serves your domain. You write a simple script to restart apache each night and pipe the logs off to your analyzer. It works.
ISP/Hosting Scenario: Each server hosts many domains. You may also have load balanced servers (multiple machines) serving each domain. A tool like this is necessary to:
1. collect all the log files from each server
2. split the logs based on the virtual host(s)
3. discard invalid entries (phishing, referrer spam, etc)
4. sort them into chronological order
5. feed logs into analyzer
6. do something with the raw logs (compress, save to vhost dir, etc)
[edit]
March 2008
BSDspot ยป Getting Awstats to Work with Qmail
by camelTo get awstats to work with qmail log files I use this little script from Bob Hutchinson called qlogs4awstats.
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