How do you connect iSCSI Block Storage through isolated VLANs?

Answer

To connect iSCSI Block Storage through isolated VLANs, complete the following steps:

1. Go to Storage > Block Storage.
    
2. Click Storage for the block storage that you want to attach to your ESXi hosts.
    
3. Scroll down and click Authorize Host as shown in the following screen shot. Ensure that the operating system type is “VMWare” when you place an order.

   

4. Add the ESXi hosts from Hardware drop-down menu. See the following screen capture.
   
5. Click Submit.
   
   After you add two ESXi hosts, your Authorized Hosts list looks similar to the following screen capture. Two ESXi hosts are authorized now.

   

   Assume that you have configured the VMkernel adapter vmk2 for iSCSI storage. The example shows that vmk0 is in MGMT Port group on Primary subnet, vmk1 is in vMotion Port group on Primary’s portable subnet and vmk2 is in iSCSI Port Group on Portable subnet - Trunked VLAN 1122. You must complete the corresponding VLAN tagging on iSCSI port group.
    

   

   Note: IBM Cloud normally provides iSCSI storage in a different subnet than your subnet so that you cannot use iSCSI port binding. Refer to the VMware document at https://kb.vmware.com/s/article/2038869
    
6. Get the storage IP address from the block storage screen. See the following screen capture:

   

7. Log in to your ESXi host through SSH and run the following command to check current routing table.
   # esxcli network ip route ipv4 list

   
   
   As you can see, the default route is set to vmk0’s gateway. If you add iSCSI storage without adding static route from VMware vSphere web client, iSCSI traffic will go through MGMT vmk0 vmkernel interface.
   
   The gateway IP address of vmk2 is 10.178.75.193 and your block storage IP address are 161.26.102.12 and 161.26.102.21

8. Run the following command to set the gateway and block storage IP addresses:
   # esxcli network ip route ipv4 add -g 10.178.75.193 -n 161.26.102.12/32

   
   
   As you can see in the previous screen capture, the first vmkping through vmk2 is not working and ping is working through vmk0. After you add a static routing, vmkping through vmk2 is working.

9. Ensure that the new static routing entry is in place by using the following command:
   # esxcfg-route -l

   

10. Repeat steps 6 - 9 for the secondary storage IP address.

    

11. Log in to vCenter server though vSphere web client and create a Software iSCSI Adapter. See the following screen capture.

    

    1. Open the vSphere vCenter web client.
        
    2. Log in to vCenter.
        
    3. Click the ESXi host that you want to configure.
        
    4. Click Manage > Storage Adapters.
        
12. Update the iSCSI IQN, which is in the control portal.

    

    Click Target > Dynamic Discovery > Add to add the iSCSI information. See the following screen capture.
    Target storage IP address: 161.26.102.12, 161.26.102.21
    CHAP authentication information: Username, Password from the portal

    

13. Provide the iSCSI Storage IP address and select Use unidirectional CHAP if required by target from the Authentication Method menu.
     
14. Deselect the Inherit settings from parent option.
     
15. Provide the CHAP credential then click OK to complete.
     
16. Repeat steps 13-15 for the secondary iSCSI target IP address. See the screen capture below for steps 13-15.

    

17. Click Rescan, select the two options that display, and click OK to re-scan all storage. See the following screen capture:

    

    
    After the re-scan process is complete, you see 2 paths are connected through two different IP addresses. See the following screen capture:

    

    You can see the disk from the Devices tab as well.

    

18. Log in to the ESXi hosts through SSH and ensure that two iSCSI connections are using the vmk2 vmkernel interface.

    

Notes

• To troubleshoot iSCSI connection, issues run tail -f /var/log/bobd.log while re-scanning the iSCSI and find the reason code, refer to VMware KB 2001449 for a specific reason code.
• Attaching IBM File Storage (NFS) to ESXi server requires same static routing procedure.