Datasheet

5.5.5.3 Configuring SEAs using the VIOS CLI

The following document describes how to set up auto mode using the command line interface,

but you can substitute sharing for the ha_mode parameter value. Refer to the following steps at:

https://www-304.ibm.com/support/docview.wss?uid=isg3T1011040

Note that step 3 and step 7 in the above document are the mkvdev –sea … command to create

the shared Ethernet adapters (SEA) has to have all of the parameters, specifically the –attr

parameters, included in the one command. Do not try to change an existing SEA to add the

attributes.

Note: Step 5 Create a virtual adapter to be used in the SEA adapter on VIOS2. EX: (ent2)

a. Give the virtual adapter the same VLAN ID (PVID) as VIOS1. EX: "1" .

b. Check the box "access external network".

c. Give the virtual adapter a higher trunk priority. EX: "2"

The Trunk Priority of 2 is critical! The default is 1, which will match the SEA already created in

the first VIOS partition, With the same trunk priority, or if you try to create the second SEA without

all of the attributes shown in step 7 of the referenced document, your VIO server will create a

broadcast storm on your network! Your network administrator will not be happy with you.

Note: To better utilize the 10 Gb Ethernet adapters that can be owned by each VIOS server,

ha_mode=sharing was implemented. The virtual Ethernet traffic handling is negotiated between

the VIOS servers as additional LANs are configured, but there is a catch. You have to enable

IEEE 802.1Q VLAN tagging on each virtual Ethernet LAN for this to work. A different port VLAN

ID (PVID) is not enough. You don’t have to specify an explicit VLAN tag, just enable the tagging

support on each virtual Ethernet adapter. Check the box labeled IEEE 802.1Q to enable tagging

and have the negotiation take place.

5.6 Redundant VIOS Networking

When implementing redundant VIOS partitions as discussed in the Dual hosting section, you also

need to consider the networking used there. The default handling of the Ethernet traffic is for the

primary VIOS to do all of it. This is referred to as ha_mode=auto. But users also wanted a way

to share the handling of the Ethernet traffic between the primary and the backup VIOS’s. This is

configured using ha_mode=sharing. You can use the HMC, SDMC or VIOS CLI do configure this.

See the steps in section “Configuring SEAs using the HMC/SDMC” to configure the SEA, but

while on that interface look for a Failover checkbox.

 Select the Failover checkbox

 Then choose the second VIOS partition and its associated Ethernet adapter (ent#).

 Ensure that a control channel, used for the heartbeat function between the VIOS’s, is

selected to be configured. NOTE: When configuring a failover VIOS, another virtual

Ethernet adapter must be created in each VIOS first which will be used as the control

channel. These virtual adapters must use a PVID that is different than the one used by

the SEA and cannot be configured for Layer-2 bridging.

5.7 Adding new devices to VIOS

VIOS does not automatically scan for new devices added after the initial boot is complete. When

a new device – such as a LUN on a storage subsystem – is added to VIOS, prompt VIOS to scan

for new devices by connecting with Telnet or SSH and using the following command: