[Yanel-dev] High availability cluster based on Apache httpd/Tomcat and NFS

[Michael Wechner]

Hi

I have recently found the following tutorials

http://www.howtoforge.com/set-up-a-loadbalanced-ha-apache-cluster-ubuntu8.04
http://www.linuxvirtualserver.org/docs/ha/ultramonkey.html
http://www.howtoforge.com/high_availability_nfs_drbd_heartbeat

whereas re storage, a SAN based on FC (Fiber Channel) or iSCSI might be 
faster though than the NFS.

Instead of using actual hardware one could of course also rent some 
virtual boxes at Amazon:

http://aws.amazon.com/ec2/instance-types/

(see also "Measuring Compute Resources" and "I/O Performance" for 
comparison with real iron),

and of course one could also setup an NFS in between these virtual 
boxes, but it is not clear to
me if Amazon is offering a SAN like storage solution, because it's not 
clear to me if an EBS can
be attached to multiple EC2 instances, because according to

http://aws.amazon.com/ebs/

it says: "A volume can only be attached to one instance at a time"

but I don't know what the following announcement means

http://aws.amazon.com/about-aws/whats-new/2010/07/13/announcing-cluster-compute-instances-for-amazon-ec2/

Cheers

Michael