admin-how-to

From Microformats Wiki
Jump to navigation Jump to search

<entry-title>admin how-to</entry-title>

This is a reference for various tasks that admins may have to perform.

web server restart

If you're reading this then either the server is up, or the server is down and you're reading a Google Cache copy (thus it's still useful to post this here).

If the web server is down, e.g. someone notes on IRC or Twitter:

  • "if any of the microformats.org website admins are on, the site is down."

Then:

  • ssh into the server
  • check for web server errors (sometimes this can reveal the source of a problem)
    • tail /var/log/httpd/error_log
  • find the apache install (it might not be where you expect it or it might have moved)
    • locate apache
  • then using the full path to "apachectl" (rather than just "apachectl" in the command)
    • sudo apachectl -k restart
  • if you get an error like:
    • (98)Address already in use: make_sock: could not bind to address 0.0.0.0:80
  • then see if there are any existing stalled restart processes by doing:
    • ps -eaf | grep http
  • if you see any processes like:
    • 1337 ? S 0:44 httpd -k restart
    • 31337 ? S 0:44 httpd -k restart
  • then kill them using their id (that first number) like:
    • sudo kill -9 1337
  • if there are too many to do individually, you can also use:
    • sudo killall -9 httpd
  • re-run the ps command:
    • ps -eaf | grep http
  • it should be the only thing running with "http" in the name, e.g.
    • 25252 pts/0 S+ 0:00 grep http
  • at this point, try restarting the apache server again:
    • sudo apachectl -k restart
  • and you should see:
    • httpd not running, trying to start
  • now try browsing to http://microformats.org/ and make sure it loads
  • report back on IRC or Twitter to whoever pointed out that the server was down.

semaphore exhaustion

This is a much rarer error state: Apache error log stating: [emerg] (28)No space left on device: Couldn't create accept lock (/etc/httpd/run/accept.lock.NNNN) (5). Thanks to http://rackerhacker.com/2007/08/24/apache-no-space-left-on-device-couldnt-create-accept-lock/ for the hint.

  • If the output of sudo ipcs -s is lots of lines of dead apache process IDs leaving semaphores behind:
    • sudo sh
    • for i in `ipcs -s | awk '{print $2}'`; do (ipcrm -s $i); done
  • you will see two lines of erroneous output:
    • ipcrm: invalid id (Semaphore)
    • ipcrm: invalid id (semid)

… and then proceed to restart as before.

server transition testing

Some things to check when transitioning to / setting up a new server.

editing your local hosts file

In order to test a new server from your local machine and still have hardcoded URL references work, you may need to manually edit your local machine's hosts file, per:

http://www.howtogeek.com/howto/27350/beginner-geek-how-to-edit-your-hosts-file/

  • Add the line: 
    64.207.154.205 www.microformats.org microformats.org
    to the hosts file on your local machine.
  • Do the flush cache tip as described below.
  • Restart your browser

Your browser should now behave *exactly* as if you'd switched actual DNS.

This makes it a very good way to test.

DNS flush cache tips

If you're using OSX, you'll probably have to run this to flush the local dns cache: 

dscacheutil -flushcache

current servers being tested

home and blog

wiki

irc bots

profiles

media

  • audio / video recordings of talks
  • ... need URLs ...

mailing list archives

  • ...

shorteners

other

  • ...

attack logs

Note any logs / summaries of attacks. Anything more than a summary should be moved to its own page.

  • 2012-02-01 openlinksw were issue excessive http requests, sufficient to unacceptably increase user access latency. banned an IP.
  • 2010-10-31 Banned demo.OpenLinkSW.com by IP, 63.119.36.50 -Rohit
  • ...

see also

Retrieved from "http://microformats.org/wiki/index.php?title=admin-how-to&oldid=45470"