- Windows Server 2012 R2
- NLB for multiple IIS
- each IIS in separate VM in VMWare vCenter, it is not known, whether both of them are on the same hardware
- 1 NIC per VM
- further VMs for database and AD DC are in the same subnet and the IIS access them
- VMs connected via vSwitch
- it is just a test environment
- pinging between the NLB nodes works
I tried unicast and multicast mode, in both cases it is working sometimes. Especially after setting up NLB in one of the two modes it works fine. However after a restart it makes trouble.
In both modes, I get the following warning in the Event log:
"NLB cluster [172.26.101.21]: NLB detected duplicate cluster subnets. This may be due to network partitioning, which prevents NLB heartbeats of one or more hosts from reaching the other cluster hosts. Although NLB operations have resumed properly, please investigate the cause of the network partitioning."
Unicast
- often just 1 of the VMs converges and the other one converges infinitely
- 1 of the NLB VMs sometimes has just limited internet access
Multicast
- 1 VM converges fast, the other one needs >= 10 minutes
- after restarting one of the VMs the virtual cluster IP is not accessible at all (neither website nor ping)
- I captured the network traffic on the client (same subnet) using Wireshark. It does not even send a HTTP request, but there are ARP requests for my virtual cluster IP and they are answered appropriately.
I only tested the access from another VM in the same subnet as client, so router limitations concerning ARP should not be a problem.
I read these articles, but they did not solve my problem (I did not follow the instructions for changing the router configuration, because even the test with a client inside the same subnet did not work):
http://kb.vmware.com/selfservice/search.do?cmd=displayKC&docType=kc&docTypeID=DT_KB_1_1&externalId=1006558
http://kb.vmware.com/selfservice/search.do?cmd=displayKC&docType=kc&docTypeID=DT_KB_1_1&externalId=1006778
http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=1556
Here my configuration, if you need further information, I will provide them:
Interface Ethernet0 Parameters ---------------------------------------------- IfLuid : ethernet_10 IfIndex : 12 State : connected Metric : 10 Link MTU : 1500 bytes Reachable Time : 38000 ms Base Reachable Time : 30000 ms Retransmission Interval : 1000 ms DAD Transmits : 3 Site Prefix Length : 64 Site Id : 1 Forwarding : disabled Advertising : disabled Neighbor Discovery : enabled Neighbor Unreachability Detection : enabled Router Discovery : dhcp Managed Address Configuration : enabled Other Stateful Configuration : enabled Weak Host Sends : disabled Weak Host Receives : disabled Use Automatic Metric : enabled Ignore Default Routes : disabled Advertised Router Lifetime : 1800 seconds Advertise Default Route : disabled Current Hop Limit : 0 Force ARPND Wake up patterns : disabled Directed MAC Wake up patterns : disabled ECN capability : application
NLB Cluster Control Utility V2.6 Cluster 172.26.101.21 === Configuration: === Current time = 24.08.2015 10:55:25 ParametersVersion = 6 CurrentVersion = V2.6 EffectiveVersion = 00000201 InstallDate = 0x55D58FB7 HostPriority = 1 ClusterName = www.example.com ClusterIPAddress = 172.26.101.21 ClusterNetworkMask = 255.255.0.0 DedicatedIPAddresses/ = 172.26.101.22/255.255.0.0 DedicatedNetworkMasks McastIPAddress = 239.255.101.21 ClusterNetworkAddress = 03-bf-ac-1a-65-15 IPToMACEnable = ENABLED MulticastSupportEnable = ENABLED IGMPSupport = DISABLED MulticastARPEnable = ENABLED MaskSourceMAC = ENABLED AliveMsgPeriod = 1000 AliveMsgTolerance = 5 MaxConnectionDescriptors = 262144 FilterICMP = DISABLED ClusterModeOnStart = STARTED PersistedStates = NONE NBTSupportEnable = ENABLED UnicastInterHostCommSupport = ENABLED BDATeaming = NO TeamID = Master = NO ReverseHash = NO IdentityHeartbeatPeriod = 10000 NumberOfRules (2): VIP Start End Prot Mode Pri Load Affinity --------------- ----- ----- ---- -------- --- ---- -------- ALL 80 80 TCP Multiple Eql None ALL 443 443 TCP Multiple Eql None === Event messages: === Could not open event log due to: The operation completed successfully.
- Edited by chipper12 Tuesday, August 25, 2015 6:16 PM