Posts Tagged SAN

Setting up & Configuring EMC VNXe3150 iSCSI SAN Storage with High.

Setting up EMC VNXe3150 iSCSI SAN Storage

Finally, the EMC VNXe3150 got installed and configured and almost ready to start transition from old EMC AX4 to the new VNXe3150. In the initial stage, found a bit difficulties to get it configured correctly as every EMC documentation speaks about something else specially when it comes to iSCSI High Availability, they mix between NFS HA and iSCSI HA. In reality, both Storage HA of NFS and iSCSI differ from each other. Simply, NFS uses Link Aggregations with LAG/LACP and iSCSI is not.


  • VNXe 3150 with dual storage processors with software version
  • Two Dell Stackable 6224 – 24 port Gigabit switches configured with Jumbo frames for iSCSI and Flow Control Enabled.
  • One – ESXi VMware ESXi 5.1.0 build-799733 host with 6 Gig pNIC’s two pNICs used for iSCSI connectivity only

Configuration on the VNXe

The configuration part is a bit of dilemma when it comes to iSCSI connectivity. In VNXe I set up two iSCSI Servers, one for Storage Processor A and one for Storage Processor B. Each SP has two IP Addresses configured for each Ethernet Interfaces, eth2 & eth3

iSCSI Server Settings-1

iSCSI Server Settings-2

iSCSI Server Settings-3








All the Ethernet Interfaces are configured with 9000 mtu size for Jumbo Frame;

MTU Config SPB

MTU Config SPB-eth3








Storage Resources Configuration

Storage Elements iSCSI Server Port IP Address MAC Address pSwitch Port VMKernel iSCSI PortGroup
iSCSI-A iSCSI_ServerA eth2 8:0:1b:57:71:3e 2/g1 iSCSI-01 vmk1
eth3 8:0:1b:82:78:dd 1/g1 iSCSI-02 vmk2
iSCSI-B iSCSI_ServerB eth2 8:0:1b:58:59:0f 2/g2 iSCSI-01 vmk1
eth3 8:0:1b:cd:f3:26 1/g2 iSCSI-02 vmk2

As you can see in the above screen shot and configuration table, each storage process have two Ethernet ports, each Ethernet port is connected to iSCSI pSwitch, eth2 in SPA matched eth2 in SPB. So since both of these interfaces are connected to the same pSwitch and same IP subnet is configured on both, single iSCSI VMkernel PortGroup on the same subnet can reach to both Storage Processors through single physical adapter “vmnic”

VNXe Connectivity Diagram

 VNXe Network Diagram










iSCSI Switches Configuration

Both network switches are configured as master and slave stackable switches, basically for this type of configuration you will not require to stack the switches as each of pair SP Ethernet are connected to the same switch. i;e SPA-Eth2 in pSwitch1 & SPB-Eth2 in pSwitch1. But with NFS configuration you will require to stack the Switches as you will need to configure LAG/LACP for true High Availability

Set up Jumbo Frames on the two iSCSI gig switches so that all the ports are using support Jumbo Frames. Below commands will let you configure all the ports with mtu size 9000

Console(config)#Interface range ethernet all

Console(config-if)#mtu 9000

ESXi host configuration

Each of the Gigs port in ESXi host is connected to the Physical iSCSI Switches. Two VMKernel PortGroups created in vSwitch1. Each of the iSCSI Kernels is mapped to the physical interface in ESXi.

Switch Name      Num Ports   Used Ports  Configured Ports  MTU     Uplinks

vSwitch1         128         8           128               9000    vmnic2,vmnic6

PortGroup Name        VLAN ID  Used Ports  Uplinks

iSCSI-02              0        1           vmnic6

iSCSI-01              0        1           vmnic2

vmk1       iSCSI-01            IPv4     00:50:56:6e:ea:87 9000    65535     true    STA                                  TIC

vmk2       iSCSI-02            IPv4    00:50:56:64:c0:6d 9000    65535

iSCSI vSwitch Ports

To check the connectivity is mapped correctly for each iSCSI PortGroup to reach the correct Ethernet Interface in the Storage Processor; vmkping with –I will allow you to specify the source interface to reach the destination iSCSI target; as this will test the whole path end-to-end from VNXe Storage, ESXi Hosts to Physical iSCSI Switches to make sure connectivity can flow with jumbo frame.

iSCSI Adapter Port Binding

Both iSCSI VMKernel portgroups has to be enabled for port bindings in the iSCSI Initiator adapter of ESXi.

iSCSI Port Bindings




Connectivity Results

# vmkping -I  vmk1 -c 50 -s 9000

PING ( 9000 data bytes

9008 bytes from icmp_seq=0 ttl=255 time=0.596 ms

9008 bytes from icmp_seq=1 ttl=255 time=0.575 ms

9008 bytes from icmp_seq=2 ttl=255 time=0.548 ms

— ping statistics —

3 packets transmitted, 3 packets received, 0% packet loss

round-trip min/avg/max = 0.548/0.573/0.596 ms

# vmkping -I vmk1 -c 50 -s 9000

PING ( 9000 data bytes

9008 bytes from icmp_seq=0 ttl=255 time=0.591 ms

9008 bytes from icmp_seq=1 ttl=255 time=0.617 ms

9008 bytes from icmp_seq=2 ttl=255 time=0.603 ms

# vmkping -I vmk2 -c 50 -s 9000

PING ( 9000 data bytes

9008 bytes from icmp_seq=0 ttl=255 time=0.634 ms

9008 bytes from icmp_seq=1 ttl=255 time=0.661 ms

9008 bytes from icmp_seq=2 ttl=255 time=0.642 ms

— ping statistics —

5 packets transmitted, 5 packets received, 0% packet loss

round-trip min/avg/max = 0.634/0.661/0.708 ms

# vmkping -I vmk2 -c 50 -s 9000

PING ( 9000 data bytes

9008 bytes from icmp_seq=0 ttl=255 time=0.694 ms

9008 bytes from icmp_seq=1 ttl=255 time=0.658 ms

9008 bytes from icmp_seq=2 ttl=255 time=0.690 ms

Add ESXi hosts to VNXe

Setup the ESXi hosts to access VNXe iSCSI SAN Storage. This can be done by browsing into the VNXe > Hosts > VMWare will allow you to find ESX hosts either by typing in the IP Address of the vCenter or the management network of the ESXi itself. Then create VMFS datastore on the VNXe and make sure you are assigning permission to the ESXi host to access the newly created LUN.

After the LUN is presented to the ESXi host and formatted with VMFS now it’s time to change the path selection through from default Fixed to Round Robin and change the Round Robin default IOPS limit in ESXi from 1000 to 1 which will allow you to utilize all the iSCSI paths.

esxcli storage nmp psp roundrobin deviceconfig set –type=iops –iops 1  –device=naa.6006048c2fb691695617fc52e06065a2

Once it’s change you will see all the paths with Active(I/O) for each LUN that changed from Fixed to Round Robin.

Path Round Robin




Failover – Failback Testing Scenarios

For the failover testing I have presented 500 GB LUN and created two Virtual Machines, and installed Windows 2008 R2 Enterprise Edition. Roles installed on this guest machine;

  • Microsoft Active Directory Role Services
  • Microsoft DNS Server Services
  • Exchange Server 2010 with all the Roles.

The second Virtual Machines are a Windows 7 Professional client with Microsoft Outlook 2010 connected to the Exchange 2010 MAPI profile. Sending and receive emails internally is operational in normal mode.

Testing Networking

I have tested failover with network issues scenarios by disconnecting one pNic “vmnic2” from the vSwitch1 that mapped to iSCSI-01 portgroup and at the same time vmkping –I vmk1 was running against both VNXe iSCSI Target IP’s SPA-Eth1 “” & SPB-Eth2 “” and ping continues well.  If a Storage Processor (SPA) fails/rebooted on VNXe, the working Storage Processor (SPB) picked up the workload that was handled by SPA.

Testing Networking-1

  • As you can see in the above screen shots, Virtual Machines Windows 7 Client continued pinging the Exchange Server and Exchange Server continued to ping Windows 7 Client.
  • Vmk1 = iSCSI-01 which mapped to vmnic2 stopped pinging to the SPA-Eth2 & SPB-Eth2.
  • LUN Paths both links mapped to vmnic2 subnet 10.90.8.x dead and 10.100.8.x paths mapped to vmnic6 ‘vmk2’ “iSCSI-02” are live and Active(I/O).

Path Round Robin-Failuer






Ping  “vmnic6” via vmk2 to &

# vmkping  -I vmk2

PING ( 56 data bytes

64 bytes from icmp_seq=0 ttl=255 time=0.229 ms

64 bytes from icmp_seq=1 ttl=255 time=0.192 ms

64 bytes from icmp_seq=2 ttl=255 time=0.238 ms

— ping statistics —

3 packets transmitted, 3 packets received, 0% packet loss

round-trip min/avg/max = 0.192/0.220/0.238 ms

~ # vmkping  -I vmk2

PING ( 56 data bytes

64 bytes from icmp_seq=0 ttl=255 time=0.235 ms

64 bytes from icmp_seq=1 ttl=255 time=0.245 ms

— ping statistics —

2 packets transmitted, 2 packets received, 0% packet loss

round-trip min/avg/max = 0.235/0.240/0.245 ms

Relink vmnic2 to vSwitch1 and ping resumed back to SPA-Eth2 & SPB-Eth2

ReLink vmnic2 vSwitch1









LUN paths resumed

Path Round Robin-Path Resumed







Testing Power Failure of VNXe Storage Processors-A & Storage Processor-B

The second test was done by removing the physical power from Storage Processor-B and initiate vmkping to both Ethernet Interface of SPB from both VMKernel vmk1 & vmk2, as a result vmkping continues as the traffic routed peer SP port.

Testing Power Failure







Result of ping after

Below result shows that Exchange VM continues to ping the Client VM during Storage Processor-B shutdown.

Result of Ping after SP-B Power Failure




Did the same with Storage Processor-A and initiated ping to both Ethernet Interfaces of SPA. Ping continues to both Ethernet Interfaces as well as pings inside each VM “Exchange Server to Client” and vice versa continues as well and Exchange Server VM didn’t give any freeze / errors in event viewer.


The VNXe3150 high availability feature at storage level and networking level ensures data protection against any single component failure in Storage Level and Networking Level.

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Unable to allocate processing resources. Error: No backup proxy is able to backup this VM. Check processing mode settings on proxies.

Are you seeing this error when you try to back up your VMs with Veeam Backup & Replication 6.5 in Direct SAN Mode? Does your Proxy Servers sees the VMFS LUNs where you are fetching the VMs Data to the Backup Mode?

This error is generated because the Veeam Configured to backup VMs via Direct SAN Access “Using source proxy VMware Backup Proxy [san] and the Proxy doesn’t have access to the VMFS LUNs.


To sort out this issue;
1. Make sure your Proxy Server can see the VMFS LUNs inside the Disk Management of the Windows.
2. Make sure the Proxy configured as Direct SAN Access.
3. Make sure the Direct SAN Access Proxy is selected in the Backup Job Configuration / Storage Section.
4. If you are still getting the error and failing to process the backup further, Open the Proxy Configuration under Backup Infrastructure -> Backup Proxies and select the desire proxy.
Right Click on the Desired Proxy and Select Properties in the Selected DataStores, select the VMFS LUNs which contains the target Backup VMs manually and try..

Hope it helps..

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