SR-IOV is relatively new feature in up-scale NICs designed to support "Software Defined Networking" (SDN), such as what is done in Azure, S3, etc. I don't expect that (at least in the short term) most companies will have a need for this. Just don't enable it. :)
[cid:[email protected]] From: [email protected] [mailto:[email protected]] On Behalf Of Miller Bonnie L. Sent: Tuesday, February 17, 2015 11:46 AM To: [email protected] Subject: [NTSysADM] RE: Anyone successfully using Microsoft NLB in guests on Hyper-V 2012 R2 host servers? Thanks Michael. BTW, we closed the case out and the MS engineer was continuing to look for documentation-they didn't have anything he could send. I asked that if they couldn't find anything existing that maybe they could at least create a KB with the information for others. >From what you found (below), do you think this is also going to potentially >affect VMs that have specific hardware requirements? For example, we have one >virtual server that has a USB HASP attached via a USB Anywhere remote device. >In order to stay licensed, the MAC address has to remain static and can't >change on this guest. I haven't tried migrating this one yet, but am now wondering from what you found if SR-IOV will also cause problems with this configuration. It matters because that is a different virtual switch than the one I removed it from, with most of my main servers connected. If I have to recreate that one, I'd like to do it early in the migration when it's going to affect fewer systems. From: [email protected]<mailto:[email protected]> [mailto:[email protected]] On Behalf Of Michael B. Smith Sent: Sunday, February 15, 2015 6:01 PM To: [email protected]<mailto:[email protected]> Subject: [NTSysADM] RE: Anyone successfully using Microsoft NLB in guests on Hyper-V 2012 R2 host servers? Thank you for the follow-up. SR-IOV didn't cross my mind. Just FYI, from RHEL: SR-IOV Virtual Functions (VFs) can be assigned to virtual machines by adding a device entry in <hostdev> with the virsh edit or virsh attach-device command. However, this can be problematic because unlike a regular network device, an SR-IOV VF network device does not have a permanent unique MAC address, and is assigned a new MAC address each time the host is rebooted. Because of this, even if the guest is assigned the same VF after a reboot, when the host is rebooted the guest determines its network adapter to have a new MAC address. As a result, the guest believes there is new hardware connected each time, and will usually require re-configuration of the guest's network settings. From: [email protected]<mailto:[email protected]> [mailto:[email protected]] On Behalf Of Miller Bonnie L. Sent: Wednesday, February 4, 2015 12:23 PM To: [email protected]<mailto:[email protected]> Subject: [NTSysADM] RE: Anyone successfully using Microsoft NLB in guests on Hyper-V 2012 R2 host servers? Quick post-back on this-NLB Unicast mode won't converge if the Virtual switch has SR-IOV enabled. I've not been able to find documentation and am still waiting to see if the MS engineer has found any over the weekend. If not, I've asked if they can at least post something up for others. The key find was a warning posted in the event log on one of the WS12R2 Host servers: Log Name: System Source: Microsoft-Windows-Hyper-V-VmSwitch Date: 1/30/2015 6:48:38 AM Event ID: 119 Task Category: None Level: Warning Keywords: User: N/A Computer: HOSTSERVERNAME.OUR.DOMAIN Description: Port BE52B143-77DD-42DF-A20F-855D033D22EB (Friendly Name: Dynamic Ethernet Switch Port) has MAC address spoofing enabled. This is not supported on the associated switch 013FACF3-700C-4CFD-904F-2CCA765AD26E (Friendly Name: My-Hyper-V-Switch-Name) because IOV is enabled. Traffic with a spoofed MAC address will not function properly. SR-IOV can only be set at switch creation, so I had to recreate the switches to fix the issue. In our case, the only traffic on this network will be NLB Unicast, so it will work. -Bonnie From: [email protected]<mailto:[email protected]> [mailto:[email protected]] On Behalf Of Miller Bonnie L. Sent: Thursday, January 22, 2015 12:59 PM To: [email protected]<mailto:[email protected]> Subject: [NTSysADM] RE: Anyone successfully using Microsoft NLB in guests on Hyper-V 2012 R2 host servers? So this AM I took the live servers offline and took copies of all the vhds for testing with and then brought them back up. If I bring any of them up on the 2012 R2 hosts I have the issue with no convergence, if I bring the same ones back up (rebuilt vm config, different name and IP) on 2008 r2 hosts they converge fine. If both cluster nodes are on 2012 R2 hosts then neither will work. Saw a thread go by this week about VM queue so tried disabling that, but it didn't help. These are Intel NICs, but because of the MAC hashing stuff that it does I thought it was worth a go. I've opened a case this afternoon-will see if they can find anything. Hopefully I've done something dumb in configuration, but it's not usually that easy when all I hear is the sound of chirping. -Bonnie From: [email protected]<mailto:[email protected]> [mailto:[email protected]] On Behalf Of Miller Bonnie L. Sent: Tuesday, January 20, 2015 3:28 PM To: [email protected]<mailto:[email protected]> Subject: [NTSysADM] Re: Anyone successfully using Microsoft NLB in guests on Hyper-V 2012 R2 host servers? I've only migrated one node of two, so haven't tried both on 2012 R2 hosts. I could take a test copy for that but didn't want to completely break things if it doesn't work,, like the first. To rephrase (typing on my phone) when I completely delete the NLB cluster, if I try to bring the migrated node up first (2012 r2 host) it will fail to converge correctly e. Redoing the same with the guest on 2008 r2 and it works as expected. The only change is the host migration and recreating the cm config. ________________________________ From: [email protected]<mailto:[email protected]> <[email protected]<mailto:[email protected]>> on behalf of Michael B. Smith <[email protected]<mailto:[email protected]>> Sent: Tuesday, January 20, 2015 2:30:33 PM To: [email protected]<mailto:[email protected]> Subject: [NTSysADM] RE: Anyone successfully using Microsoft NLB in guests on Hyper-V 2012 R2 host servers? Just to ensure I understand - the problem occurs when you split the WNLB cluster across two versions of Hyper-V? It works OK on 2008R2 and on 2012R2, but not when split? From: [email protected]<mailto:[email protected]> [mailto:[email protected]] On Behalf Of Miller Bonnie L. Sent: Tuesday, January 20, 2015 5:10 PM To: '[email protected]' Subject: [NTSysADM] Anyone successfully using Microsoft NLB in guests on Hyper-V 2012 R2 host servers? Just started the process of migrating guest machines from our 2008 R2 Hyper-V cluster to the new 2012 R2 cluster the weekend before last. Doing some legwork on this migration as we are also migrating to some new storage and I don't (currently) have an interim 2012 server for importing the VM config-might have to try getting one of those. Not a big deal, we don't have snapshotting or too much fancy config so I'm just recreating VM config and the NIC along the way-have done this more times than I can count with both 2008 and then 2008 R2. All servers are migrating fine, except when I go to set up a server that is part of a Unicast NLB cluster. Am I missing something, or does it just not work the same? I have two sets (each in 2 node clusters) and neither will work on the new 2012 R2 hosts, but work on 2008 R2 hosts with what I think is similar/identical prior config. Example: -2-node NLB cluster WS12 R2 Guest OS -Unicast mode, servers on the same subnet, cluster address on the same subnet. -One vm (working) is still living on the old WS08 R2 Hyper-V hosts. The other (not working) is on 2012 R2 Hyper-V hosts. -The guest machine will work "normally" (can ping/connect/etc) until I try to add back to the NLB cluster, at which time network communications seem to quit working. The virtual nic inside of the guest LOOKS like everything is correctly set & bound for NLB. -New virtual NIC IS set correctly to enable mac address spoofing. I keep going back to this as the problem looks just like what happens if you fail to have this set correctly, but it is there. Have even recreated the NIC again in the guest to make sure. -Problem is not dependent on failover clustering-it happens outside of the failover cluster on either individual Hyper-V host server. -Error message after configuring NLB will either be host unreachable or NLB not bound. -Deleted & recreated NLB cluster on old (working) guest early this AM to make sure it really is from the migration. That one recreates fine, new one has same problems. -Had IPv6 set up-removed IPv6 addresses from guests & unchecked boxes for bindings, recreated cluster with no IPv6 in play (short of disabling in registry) and get the same errors only on the migrated server. Does anyone have this working? Trying to figure out if I need to open a premier case as there could be some new setting in 2012 R2 interfering, or something not right with the host OS config/switch (although I'm not really using any of the fancy new features for switching.) We have several NLB clusters that will need to be migrated. TIA, Bonnie
