File Cluster VS VM
Is anyone creating host based file clusters anymore? or are they switching to HA VMs instead?
thanks
回答
I thought this would spark a really good discussion... and it's a really good topic. Some people who haven't bought into virtualization (YET) argue it should be on bare metal... and others argue that a File Server is the perfect workload to put in a VM. I would tend to agree with the later, except for maybe a massive File Server with tens of thousands of users pounding it, where traditionally the server becomes I/O bound.
By putting the workload in a VM it brings a number of wins, but lets discuss just the HA characteristics
Planned Downtime:
- Live Migration - Move the File Server VM to another server with zero client downtime
- Move Group - Failover the File Server from one server to another, with seconds of downtime to clients
Unplanned Downtime:
- Restart VM - If the host goes down unexpectedly, the VM is restarted on another host. You have to cold start the guest OS and then start File Services and SMB sahres
- Failover - The SMB shares are failed over to another server. Results in less downtime, as the OS doesn't have to be cold booted.
There are really 2 key values that a Cluster File Server brings, over putting it in a VM:
- Workload Health Monitoring - The Cluster service is actively monitoring the health state of the Server service and SMB shares, if they become unavailable then the shares are failed over to another server
- Workload Mobility - Putting a workload in a VM provides a great story for patching of the host OS, as you can just live migrate VM's off. But what if you need to patch the Guest OS in the VM? That's the biggest difference and win with a File Cluster, is that when you need to patch the OS you can move the shares somewhere else.
With that said... it's really a question if the downtime associated with patching the guest OS is an issue for you. Also remember that you can combine the technologies, and do "Guest Clustering". Then you have the best of all worlds... you can create File Clusters from the VM's, and failover SMB shares to another VM for mobility in the event that you need to do patching of the guest OS.
It's all really a business decision in what are the service level agreements you need to accomplish... putting all your standalone File Servers into VM's is going to increase the overall availability of them by the HA characteristics they bring. So I think that's a no-brainer. The next question becomes around what is the right answer for your most mission critical File Servers, and what does your business require.
My 2 cents,
Elden- 回答の候補に設定WPJBMVP2009年11月30日 2:39
- 回答としてマークJM Networking 2009年12月1日 22:29
すべての返信
- What is the "host based file clusters" you mentioned?
sorry - I meant a regular W2008-R2 two node cluster (where you run the wizard and select File Server Cluster) - not within a VM - but at the parent level.- No problem. You can do that.
I guess what Im asking (and I know every situation is a little different) - is: are there any advantages to a File Server Cluster over a HA VM (running in W2008 Hyper-V R2) (performance or otherwise)
thanksI thought this would spark a really good discussion... and it's a really good topic. Some people who haven't bought into virtualization (YET) argue it should be on bare metal... and others argue that a File Server is the perfect workload to put in a VM. I would tend to agree with the later, except for maybe a massive File Server with tens of thousands of users pounding it, where traditionally the server becomes I/O bound.
By putting the workload in a VM it brings a number of wins, but lets discuss just the HA characteristics
Planned Downtime:
- Live Migration - Move the File Server VM to another server with zero client downtime
- Move Group - Failover the File Server from one server to another, with seconds of downtime to clients
Unplanned Downtime:
- Restart VM - If the host goes down unexpectedly, the VM is restarted on another host. You have to cold start the guest OS and then start File Services and SMB sahres
- Failover - The SMB shares are failed over to another server. Results in less downtime, as the OS doesn't have to be cold booted.
There are really 2 key values that a Cluster File Server brings, over putting it in a VM:
- Workload Health Monitoring - The Cluster service is actively monitoring the health state of the Server service and SMB shares, if they become unavailable then the shares are failed over to another server
- Workload Mobility - Putting a workload in a VM provides a great story for patching of the host OS, as you can just live migrate VM's off. But what if you need to patch the Guest OS in the VM? That's the biggest difference and win with a File Cluster, is that when you need to patch the OS you can move the shares somewhere else.
With that said... it's really a question if the downtime associated with patching the guest OS is an issue for you. Also remember that you can combine the technologies, and do "Guest Clustering". Then you have the best of all worlds... you can create File Clusters from the VM's, and failover SMB shares to another VM for mobility in the event that you need to do patching of the guest OS.
It's all really a business decision in what are the service level agreements you need to accomplish... putting all your standalone File Servers into VM's is going to increase the overall availability of them by the HA characteristics they bring. So I think that's a no-brainer. The next question becomes around what is the right answer for your most mission critical File Servers, and what does your business require.
My 2 cents,
Elden- 回答の候補に設定WPJBMVP2009年11月30日 2:39
- 回答としてマークJM Networking 2009年12月1日 22:29
- great topic and I agree fully with you, if you need additional redundancey ontop of that deploy 2 HAVMs and then DFSR between them with AD DFS and you are completely set...
will
William Bressette, Network Architect, Horn IT Solutions, http://wpjsplace.spaces.live.com/blog- 回答の候補に設定WPJBMVP2009年11月30日 2:40
