Linux – Dead simple tool to administer users on multiple servers

Your cluster sounds more like an HPC cluster than an OLTP one like mine, but I think the setup I'm using would work for you too. I call it the "mpdehaan trifecta" because thats the ircnick of the guy who wrote or manages the three tools involved.

1.) Cobbler for base-build provisioning. Cobbler is a project that aims to be the intersection of your kickstart, pxe, yum-repo, dhcp, dns, etc systems. Its by far the easiest way to get a kickstart setup up and running, and you can grow into the other features as needed.

2.) Puppet for configuration management. Ideally your cobbler built hosts are very barebones configs that know just enough to phone home to your puppet server on startup. Puppet will then apply your configuration settings and keep them consistent across your environment in perpetuity.

3.) Func for ad-hoc commands to multiple machines in parallel. For instance "deploy a new svn checkout of the code and restart apache". Its pretty easy to just use func to call the same bash command on a group of servers much like cluster-ssh. If you really want to get into it you can write your own modules for it with some really simple python.

All three of these tools have good wiki's and active irc channels for help on freenode.

You should use a group for each website. And make all users that need write access to be members of the respective group.

groupadd site1_com
mkdir /var/www/www.site1.com
chgrp site1_com /var/www/www.site1.com
find /var/www/www.site1.com -type d -print0|xargs -0 chmod g=rwxs
chmod -R g+rw /var/www/www.site1.com
usermod -aG site1_com user1

Now each time the users are creating files under /var/www/www.site1.com folder they should use the umask 0002 (in ~/.bashrc or in the deployment script) or they should set the permission for the group to have read write access chmod -R g+rw /var/www/www.site1.com 2>/dev/null.

Another solution to set the permissions would be to use dnotify. Create /usr/local/sbin/dnotify_handler-reset_perms.sh script with the following content:

#! /bin/sh
CHANGED_FOLDER=$1
find $CHANGED_FOLDER -maxdepth 1 -mmin 0 -not -perm -g+w -exec chmod g+w {} \;

And add to /etc/rc.local:

dnotify --recursive /var/www/www.site1.com --create --execute --background /usr/local/sbin/dnotify_handler-reset_perms.sh