vNIC Failover configuration in command line - the faster way.

Hereby explain both methods to achieve our goals ie. configure vNIC clients in LPARs having 2 channels in failover mode.

Let’s first explain the way to configure vNIC in DLPAR mode and we know, we do have a method to sync the DLPAR change with the current running profile by setting sync_curr_profile to 1.

To configure vNIC on a SR-IOV adapter, first the adapter should be in shared mode. We can switch a SR-IOV adapter to shared mode using the below hmc command:

chhwres -m <managed-system> -r sriov --rsubtype adapter -o a -a "slot_id=<drc_index-of adapter>"

Here the drc_index of the SRIOV adapter can be found using below command: (This command display all the IO adapters on the managed system. Choose the drc_index of the SR-IOV adapter using for vNIC configuration)

 lshwres -r io --rsubtype slot -m <managed-system>

Once moved the SR_IOV adapter to the shared mode, below command (which list all the SR-IOV adapters on the managed system) will show the attribute ‘config_state’ of the SR-IOV adapter as ‘sriov’, otherwise it will be shows as ‘dedicated’.

lshwres -m <managed-system> -r sriov --rsubtype adapter

Please note that the adapter should be in shared mode to create VF and/or vNICs on them.

Below hmc command can be used to create a nVIC and add it to the running profile.

chhwres -r virtualio -m <managed-system> -o a -p <partition-name> --rsubtype vnic -a "backing_devices=value "

Here the ‘partition-name’ is the vNIC client partition name on which we are creating the vNIV.

Let’s elaborate the format of ‘value‘ for the attribute ‘backing_device’ in detail. Below is its format:

sriov/vios-lpar-name/vios-lpar-ID/sriov-adapter-ID/sriov-physical-port-ID/
[capacity][/[failover-priority][/ [max-capacity]]]

sriov – it is always ‘sriov’ to mention vNIC creating out of a VF from a SR-IOV adapter.

vios-lpar-name - Name of the VIOS partition which serves the vNIC client. Here is where the VF from SR-IOV assigned to.

vios-lpar-ID – The partition ID of the VIOS partition which serves the vNIC client.

                Note: either vios-lpar-name or vios-lpar-ID is optional, but the ‘/’ must be present.

 sriov-adapter-ID – The adapter_id of the SR-IOV adapter using to create VF for vNIC

sriov-physical-port-ID – The physical port ID of the above adapter on which we are creating VF for vNIC.

Note:  sriov-adapter-ID and sriov-physical-port-ID can be seen using any of the below commands, based on the SR-IOV adapter type:

For RoCE adapter:

lshwres -m <managed-system> -r sriov --rsubtype physport --level roce

For converged ethernet adapter:

lshwres -m managed-system> -r sriov --rsubtype physport --level ethc

For ethernet adapter:

lshwres -m <managed-system> -r sriov --rsubtype physport --level eth

 
[capacity] – It is an optional value (default is 2). Here we can specify the percentage of the physical port capacity to be assigned to the VF and hence to the vNIC.

[max-capacity] – It is an optional value (default is given capacity). Here we can specify the maximum percentage of the physical port capacity that can be assigned to the VF/vNIC.

[failover-priority] – This value specifies the priority of the backing_device (VF) and has meaning when there are more than one baking_devices to the vNIC. It is an optional value and if omitted the default value 50 is taken. The range of values are from 1 to 100, 1 being the highest priority and 100 the lowest.

If need more than one backing devices to a vNIC (which is needed in the case of vNIC failover setup), a comma separated list of ‘values’ in the above format should be given, in that case the attribute name/value pair must be enclosed in double quotes.

Let’s create a vNIC failover setup as shows in the below diagram. Here we create a vNIC on the LPAR named ‘LPAR1’ having 2 different backing devices. Each backing device is served by separate VIOSes named ‘VIOS1’ and ‘VIOS2’. And each VIOS using separate SR-IOV adapters having 2 physical port.

Here the channel with green colour is the primary/active channel (so given high failover_priority value 50 to it) and the channel in red colour is inactive. The inactive channel will be active only when the primary channel fail.

Consider the adapter ID of the adapter in VIOS1 is 1 and its port 0 having ID 0 is using. Similarly, consider the adapter ID of the adapter in VIOS2 is 2 and its port 1 having ID 1 is using. Then the following command can be used to create this vNIC:

chhwres -r virtualio -m <managed-system> -o a -p LPAR1 --rsubtype vnic -a "\"backing_devices=sriov/VIOS1//1/0//50,sriov/VIOS2//2/1//60\""

Please note here the nested double quote characters need to be preceded by an escape character in this shell. Also, we omitted the optional values vios-lpar-ID, capacity and max-capacity.

After this running ‘cfgmgr’ on LPAR1 will show up the vNIC adapter on them like below:

ent1   Available  Virtual NIC Client Adapter (vnic)