[Deploying Sakai] new Rutgers configuration

[Charles Hedrick]

Since I asked for advice on configuration, I thought I should tell you how we ended up. We've tuned only

vm.overcommit_memory = 2
vm.overcommit_ratio = 80

in /etc/sysctl.conf

and

root	 	 -	nofile		10000
* 		 -	nofile		8192

in /etc/security/limits.conf

We're now running in Ubuntu server on 6 Citrix Xen VMs, We will use them in two banks of three. When we want to do a deploy, we'll bring up 3, and set the old 3 to not allow new logins. (That requires a Rutgers patch to login to be fully effective.) That makes things pretty invisible.

[The reason for Ubuntu server is that for some other projects we need more up to date software than Redhat/Centos. Since we supply Java and Tomcat as part of the Sakai deploy, our Sakai instances really only depend upon the Linux kernel.]

The VM's are running on HP blades. They're pretty substantial: two Intel X5660 with  72 GB of memory.

The next step will be moving our Mysql servers to Linux. 

We're currently also planning to virtualize storage, so we are considering (with some trepidation) running the database systems with a Dell md3600i connected to the blade system at 10 Gbps, and a set of 8 disks running as RAID 10 (to be used for production databases, test databases, and probably some of the VMs for which we think performance might be an issue).

I'd be curious whether anyone else has experience running a database over 10 Gbps  iSCSI.

(User files go on a Netapp for the production server, our own storage for development systems.)