SQL server 2008 R2 with IIS on same machine and mirroring

Question

I want to install SQL server 2008 R2 and IIS on same server with a mirroring configuration with principal/mirror/witness setup. Both principal and mirror servers will have IIS and SQL server. My question is twofold:

1) Will additional ram to the principal server be enough for smooth operation? Here we can assume a payload of about 50-100 http requests per second and flat database structure. Storage is RAID 5 or 10. Will it be better to have more than one CPU, is one multi-core CPU good enough?

2) Will automatic fail-over work for IIS as well as SQL server? for example if IIS crashes (or something else in the OS besides SQL server (some service, power supply, etc..., but no hard-disk failure)).

Thanks in advance.

Answer 1

If your budget and timeline allows it, I would strongly suggest separating the IIS and SQL Server onto two separate servers - virtualisation is fantastic for this. On the one hand, IIS connecting to SQL Server via shared memory is lightning fast, you've got to weigh up the security, isolation, and the pain of troubleshooting a shared box.

Answer 2

IIS is not cluster-aware, however, it supports high availability via NLB. Here's an article that may help you: http://learn.iis.net/page.aspx/511/achieving-high-availability-and-scalability---arr-and-nlb/

Regarding server scaling, additional RAM is always good, although that depends on how much you currently have, how much RAM the SQL server eats up, etc. As for CPU, I'd go for dual CPU, as it's more scalable in the future.