HP Integrity Virtual Machines Version 4.2 Release Notes

7.2.9 Do Not Use the HP A5506B PCI 10/100Base-TX 4 Port Interface for Virtual
Networking
Host to guest connectivity might not be reliable when using the HP A5506B PCI 10/100Base-TX
4 Port interface for guest networking.
7.2.10 Integrity VM V4.1 Does not Support Gelan Drivers
Gelan drivers are not supported with Integrity VM Version 4.1 and later.
7.2.11 MAC Address Validation Can Be Enhanced
When you add a virtual NIC to your guest, Integrity VM checks to make sure the MAC address
is unique.
By default, Integrity VM makes three attempts (each with a one-second timeout) to determine
the validity of the MAC address for the virtual NIC. This process can result in up to ten seconds
of delay for each defined virtual NIC. To speed up this processing, add the following tunable to
the /etc/rc.config.d/hpvmconf configuration file:
HPVMMACADDRFRAMES=n
Where n is the number of attempts (1 to 30). The default is 3. A value of 1 or 2 increases
performance at the risk of missing a response from a slow NIC.
You can set the HPVMMACADDRFRAMES tunable to zero (0), which completely eliminates the MAC
address verification. However, HP recommends that you do so only after you configure all of
your guests and confirm that there are no conflicts with MAC addresses in your network
environment.
To boost virtual network performance, create additional vswitches and allocate them across
guests.
7.2.12 Auto Port Aggregation (APA) is Supported on the VM Host, Not on the Guest
Integrity VM does not support running APA on a guest. You can run APA on the VM Host.
APA can be configured on the VM Host to provide a highly available LAN for the vswitch (APA
in active/passive mode) or to increase the bandwidth of the vswitch LAN (APA active/active
mode). Before you stop APA, use the hpvmnet -h command to halt the vswitch. If you do not
halt the vswitch first, the hpvmnet command reports an incorrect MAC address for the vswitch.
7.2.13 Do Not Run Applications that Set Network Devices into Promiscuous Mode
Vswitches must not be connected to network devices that are set to promiscuous mode. Do not
run applications like tcpdump on the VM Host on interfaces that are used for virtual switches.
7.2.14 Guest and Host Communication
Checksum offloading (CKO) is not supported. On most of the physical interfaces that are not of
10 Gigabyte type, CKO is turned off by default. Consult your interface card documentation for
details.
Turning on CKO can cause host-to-guest connections as well as guest-to-host communication
over a VLAN to fail. If you are receiving failures with host-to-guest connections or guest-to-host
communication using a VLAN, ensure that the CKO is turned off in the host interface driver. If
that does not fix the problem, reboot the vswitch.
To turn off the CKO on the VM Host, identify the PPA of the network interface for the vswitch
using the hpvmnet command. For example:
# hpvmnet
Name Number State Mode PPA MAC Address IP Address
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7.2 Known Issues and Information 71