+1 We're presently running somewhere around 100 VMs on an IBM Blade Center, all on iSCSI over 1.0 Gig Ethernet through a Cisco 3750 stack to our EMC NS20. we have 4 Gig ports per blade - two for network traffic, and two for iSCSI traffic back to the SAN.
We serve approximately 400 end users the following apps over this environment: Exchange 2007 (one CAS and one Mailbox), light duty SQL, eClinicalWorks EMR (Front end and ancillary servers, but not the primary database server) and other applications. While we might get better performance out of Fiber Channel, our biggest bottlenecks seem to be RAM, CPU, and disk -- in that order. RAM and CPU are inherent limitations of the physical ESX hosts. Whenever we decide to refresh our physical host infrastructure, I'm sure that will help considerably. At tha point we'll probably be looking at 10 Gig ethernet. Price to performance, my gut leans toward iSCSI over Ethernet instead of FC, but in the end it depends on your exact needs. The following links below from some of our peers (myself included, in the first article) may help. The second article talks specifically about your initial question of iSCSI vs Fibre Channel. Also, don't be confused by the difference in disks, versus the diference in SAN. You can have Fibre Channel disks in a SAN that is connected via iSCSI. http://www.biztechmagazine.com/article/2009/11/san-plan http://www.biztechmagazine.com/article/2008/11/sans-rest-us Hope this helps, Jonathan L. Raper, A+, MCSA, MCSE Technology Coordinator Eagle Physicians & Associates, PA www.eaglemds.com<http://www.eaglemds.com/> [email protected]<mailto:[email protected]> ________________________________ From: Andrew S. Baker [[email protected]] Sent: Monday, January 31, 2011 11:43 AM To: NT System Admin Issues Subject: Re: iSCSI SANs vs FibreChannel SANs iSCSI will work just fine for hosting a VM environment, as well as some other workloads. If you already have a FC infrastructure, then that's not a bad reason to go there, but iSCSI is very mature and stable and good performance if you don't purchase the cheapest equipment you can find. First, as others have pointed out, you need to size up your needs... ASB (My Bio via About.Me<http://about.me/Andrew.S.Baker/bio>) Exploiting Technology for Business Advantage... On Mon, Jan 31, 2011 at 11:32 AM, Oliver Marshall <[email protected]<mailto:[email protected]>> wrote: Well, there will be maybe 3 VMs running on each host, most likely VM will have a redundant ‘spare’ running on the other physical host. The largest will be about 400GB+ of space running Exchange 2010 for about 100 users. Then perhaps a DC and a file server, and the latter will just be acting as a witness server for the Exchange DAG servers. I like the idea of iSCSI franky but experience of the s*** end of the market has put me off. Saying that the cost of the FC based setup puts me off even more :) Olly From: John Cook [mailto:[email protected]<mailto:[email protected]>] Sent: 31 January 2011 16:26 To: NT System Admin Issues Subject: RE: iSCSI SANs vs FibreChannel SANs I have 3 MD3000/3200i SANs and they work wonderfully. That being said I found that while the fiber has better throughput (we also have an old 2Gb EMC AX150 fiber SAN) It was a lot more expensive to set up (Fiber switches aren’t cheap) and of course you need some marginal capability in configuring said switch. John W. Cook System Administrator Partnership For Strong Families 5950 NW 1st Place Gainesville, Fl 32607 Office (352) 244-1610 Cell (352) 215-6944 MCSE, MCP+I, MCTS, CompTIA A+, N+, VSP4, VTSP4 From: Richard Stovall [mailto:[email protected]<mailto:[email protected]>] Sent: Monday, January 31, 2011 11:22 AM To: NT System Admin Issues Subject: Re: iSCSI SANs vs FibreChannel SANs Not a direct answer, but another shared storage option you could consider for that setup is an MD3XXX. On Mon, Jan 31, 2011 at 11:13 AM, Oliver Marshall <[email protected]<mailto:[email protected]>> wrote: Hi Chaps We’re buying some bits to build a basic VM platform so that we can get rid of some old rack servers here. Being new to decent SANs (we have some crappy iscsi hardware that we just use for dumping scrap data on) what are peoples thoughts of iSCSI SANs vs FibreChannel SANs? We are planning on having two physical hosts (probably Dell PE710s running either Hyper-V or ESXi) with a lump of shared storage on a SAN but we are at odds here as to whether we should go iSCSI or FC. Any comments or suggestions? Olly ~ Finally, powerful endpoint security that ISN'T a resource hog! ~ ~ <http://www.sunbeltsoftware.com/Business/VIPRE-Enterprise/> ~ --- To manage subscriptions click here: http://lyris.sunbelt-software.com/read/my_forums/ or send an email to [email protected]<mailto:[email protected]> with the body: unsubscribe ntsysadmin ________________________________ Any medical information contained in this electronic message is CONFIDENTIAL and privileged. It is unlawful for unauthorized persons to view, copy, disclose, or disseminate CONFIDENTIAL information. This electronic message may contain information that is confidential and/or legally privileged. It is intended only for the use of the individual(s) and/or entity named as recipients in the message. If you are not an intended recipient of this message, please notify the sender immediately and delete this material from your computer. Do not deliver, distribute or copy this message, and do not disclose its contents or take any action in reliance on the information that it contains. ~ Finally, powerful endpoint security that ISN'T a resource hog! ~ ~ <http://www.sunbeltsoftware.com/Business/VIPRE-Enterprise/> ~ --- To manage subscriptions click here: http://lyris.sunbelt-software.com/read/my_forums/ or send an email to [email protected] with the body: unsubscribe ntsysadmin
