Testking VCP-410
o MAC Address Changes - the guest OS changes the MAC address of the adapter to anything other than what is in the .vmx
o Forged Transmits - Outbound frames with a source MAC address that is different from the one set on the adapter are dropped.
o Traffic shaping
o Traffic shaping policy is defined by three characteristics: average bandwidth, peak bandwidth, and burst size. VCP-410 questions
o ESX shapes outbound network traffic on vSwitches and both inbound and outbound traffic on a vNetwork Distributed Switch.
o Peak bandwidth cannot be less than the specified average bandwidth.
o NIC Teaming (Load balancing and failover)
o Load Balancing
1. Route based on the originating port ID — Choose an uplink based on the virtual port where the traffic entered the virtual
switch.
2. Route based on ip hash — Choose an uplink based on a hash of the source and destination IP addresses of each packet.
3. Route based on source MAC hash — Choose an uplink based on a hash of the source Ethernet.
4. Use explicit failover order — Always use the highest order uplink from the list of Active adapters which passes failover
detection criteria.
o IP-based teaming requires that the physical switch be configured with etherchannel. For all other options, etherchannel should
be disabled.
o Incoming traffic is controlled by the load balancing policy on the physical switch
o Network failover detection
o Link Status only
o Beacon probing - Do not use beacon probing with IP-hash load balancing.
o Notify Switches - a notification is sent out over the network to update the lookup tables on physical switches. In almost all cases, this
process is desirable for the lowest latency of failover occurrences and migrations with VMotion. Do not use this option when the
virtual machines using the port group are using Microsoft Network Load Balancing in unicast mode.
o Failback - determines how a physical adapter is returned to active duty after recovering from a failure. If failback is set to Yes
(default), the adapter is returned to active duty immediately upon recovery.
o Failover Order
1. Active Uplinks
2. Standby Uplinks
3. Unused Uplinks VCP-410 dumps
o When using IP-hash load balancing, do not configure standby uplinks.
o VLAN - The VLAN policy allows virtual networks to join physical VLANs - vNetwork Distributed Switch only (dvPorts).
o Port blocking policies - vNetwork Distributed Switch only (dvPorts).
o VMware uses the Organizationally Unique Identifier (OUI) 00:50:56 for manually generated addresses. You must set them in a virtual
machine’s configuration file: ethernet.addressType=”static”
o Jumbo frames must be enabled at the host level using the command-line interface to configure the MTU size for each vSwitch.
o TCP Segmentation Offload (TSO) is enabled on the VMkernel interface by default, but must be enabled at the virtual machine level.
o To enable TSO at the virtual machine level, you must replace the existing vmxnet or flexible virtual network adapters with enhanced vmxnet
virtual network adapters. This might result in a change in the MAC address of the virtual network adapter.
o To check whether TSO is enabled on a particular VMkernel networking interface use the esxcfg-vmknic -l command. The list shows
each TSO-enabled VMkernel interface with TSO MSS set to 65535.
o If TSO is not enabled for a particular VMkernel interface, the only way to enable it is to delete the VMkernel interface and recreate the
interface.
o Jumbo frames up to 9kB (9000 bytes) are supported.
o Use the vicfg-vswitch -m command to set the MTU size for the vSwitch.
o Enabling jumbo frame support on a virtual machine requires an enhanced vmxnet adapter for that virtual machine.
o NetQueue in ESX takes advantage of the capability of some network adapters to deliver network traffic to the system in multiple receive
queues that can be processed separately. This allows processing to be scaled to multiple CPUs, improving receive-side networking
performance.
o NetQueue is enabled by default.
o ESX supports a direct PCI device connection for virtual machines running on Intel Nehalem platforms. Each virtual machine can connect to up
to 2 passthrough devices. Passed VCP-410
o The following features are unavailable for virtual machines configured with VMDirectPath:
o VMotion
o Hot adding and removing of virtual devices
o Suspend and resume
o Record and replay
o Fault tolerance
o High availability
o DRS (limited availability; the virtual machine can be part of a cluster, but cannot migrate across hosts)
o Software-initiated iSCSI is not available over 10GigE network adapters in ESX.
