A Machine/Job Features Key/Value Store based on CouchDb

This twiki provides information on the setup and administration of a machine/job features key/value store based on couchdb. Such an implementation is mainly targeted for cloud infrastructures and can be run both within the infrastructure or outside (e.g. for commercial providers).

Setup

The following hardware/software characteristics were used in order to test and run an installation so far

Tip: any hostname can be used but the name wlcg-mjf is a default in the administration script and as such would not need to be specified on the command line everytime.

Info: the hardware characteristics above are on the upper bounds, some 100.000 key/value entries would use some 500 MB of disk space, also the memory and cpu requirements can probably be relaxed. Twiki will be updated with more info when a new test was executed.

After installation of the couchdb package the following steps are advised to be executed

Make couchdb accessible

By default the http interface can only be accessed from within the server node. Edit file /etc/couchdb/local.ini and put

bind_address = 0.0.0.0

to make the web service also accessible from outside. After this you may first start couchdb from init.d with

/etc/init.d/couchdb start

Open the firewall

Couchdb http will listen on port 5984 by default. Change your firewall settings with

iptables -I INPUT -p tcp --dport 5984 -j ACCEPT

(in order to make them persistent you may want to put this line into /etc/rc.local)

Start couchdb

by launching

/etc/init.d/couchdb start

If you now point your browser to your couchdb server at e.g. http://wlcg-mjf:5984 the browser should return with a message a la

{"couchdb":"Welcome","version":"1.0.4"}

Administration tool

Setup of Couchdb

1 - Deploy a machine, for the initial tests a virtual machine with 4GB RAM, 2 CPUs and 40 GB Disk was used. 2 - Install couchdb on the server, so far tested with version 1.0.4 3 -

-- StefanRoiser - 30 Apr 2014