Using HP Serviceguard for Linux with VMware virtual machines - Technical white paper

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When NIC teaming is configured in fault-tolerant mode, and one of the underlying physical NICs fails or its cable is
unplugged, ESX Server detects the fault condition and automatically moves traffic to another NIC in the bound
interfaces. This eliminates any one physical NIC as a single point of failure, and makes the overall network connection
fault tolerant. This feature requires the beacon monitoring feature (see document 1), of both the physical switch and
ESX Server NIC team to be enabled. (Beacon monitoring
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allows ESX Server to test the links in a bond by sending a packet
from one adapter to the other adapters within a virtual switch across the physical links.)
VMware recommends switches that are compatible with 802.3ad, but ESX NIC teaming will work with regular switches
and will still support the outbound load balancing and failover. Performance is not guaranteed if you deploy enterprise
switches without link aggregation features.
Serviceguard requirement: Serviceguard requires a highly available network for applications. Use VMware NIC teaming
at the host level as described above for the networks used by applications running in the VMware guests. Do not use NIC
teaming at the guest level. You can configure NIC teaming from the Virtual Infrastructure client or from the command
prompt of the ESX host.
Configuring shared storage
A disk array can be seen as a centralized storage pool for servers. Data from multiple servers is stored in dedicated areas
called logical unit numbers (LUNs). To accommodate scenarios where external physical machines must share block level
data with a virtual machine, ESX Server allows raw LUNs to be presented to the virtual machine by means of Raw Device
Mapping (RDM). Serviceguard with virtual machine nodes is supported only with RDM in which the virtual machine can be
configured to use storage in nearly the same way as physical device.
To modify the configuration of a virtual machine, it must be powered down. To add a LUN to a virtual machine in RDM
mode, the first step is to invoke the add hardware wizard. On a vSphere Client,
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you can right-click on the node to which
you need to add the disk and select Edit Settings to get the wizard started. (See figure 1)
Figure 1. Start the wizard by selecting Edit Settings
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Turning on beacon monitoring is reported to have problems. People have completely lost access to ESX server, and a Cisco white paper recommends
against turning this on as it sometimes generated false failures.
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In this paper, we have used vSphere Client 4.1.0. The screens might look different on other versions.