Notes for Storage Guide 01

Load Balancing and Failover Policy

 

You can edit your load balancing and failover policy by configuring the following parameters:

 

Load Balancing policy determines how outgoing traffic is distributed among the network adapters associated

with a switch or port group.

 

NOTE Incoming traffic is controlled by the load balancing policy on the physical switch.

 

Failover Detection controls the link status and beacon probing.

Beaconing is not supported with guest VLAN tagging.

 

Network Adapter Order can be active or standby.

List down one of the reason why you should enable port fast

In some cases, you might lose standard switch connectivity when a failover or failback event occurs.

This causes the MAC addresses used by virtual machines associated with that standard switch

to appear on a different switch port than they previously did. To avoid this problem, put your

physical switch in portfast or portfast trunk mode

 

In network detection failover detection, what are the limitations of “Link Status Only”

This policy does not detect configuration errors, such as a physical switch port being blocked by

spanning tree or misconfigured to the wrong VLAN or cable pulls on the other side of a

physical switch. This policy relies solely on the link status that the network adapter provides.

This option detects only failures, such as cable pulls and physical switch power failures.

 

 

In network detection failover detection, when it is recommended not to use beacon Probing

It is recommend not using beacon probing when you are using IP hash load balancing policies.

Beacon probing sends out and listens for beacon probes on all NICs in the team and uses this

information, in addition to link status, to determine link failure. This option detects many of

the failures mentioned above that are not detected by link status alone.

 

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In almost all cases, Notify Switches policy is set to Yes as it is desirable for the lowest

latency of failover occurrences and migrations with vMotion. But there is one use case

where it is recommended setting Notify Switches to No?

=>If you are going to use Microsoft Network Load Balancing in unicast mode, it is recommended

to set this option to No.

 

When you select Yes, whenever a virtual NIC is connected to the standard switch or whenever

that virtual NIC’s traffic is routed over a different physical NIC in the team because of a failover

event, a notification is sent over the network to update the lookup tables on the physical switches.

 

In which two cases you should not keep any network adapter in Standby Adapters list

=>When you are using iSCSI Multipathing, your VMkernel interface must be configured to have

one active adapter and when using IP-hash load balancing.

 

Security Policy

 

Networking security policies determine how the adapter filters inbound and outbound frames.

The three elements of the security policy are promiscuous mode; MAC address changes, and forged transmits.

 

In nonpromiscuous mode, a guest adapter listens only to traffic forwarded to own MAC address.

In promiscuous mode, it can listen to all the frames. By default, guest adapters are set to nonpromiscuous mode.

 

In Mac Address Changes If you set the MAC Address Changes to Reject and the guest operating system

changes the MAC address of the adapter to anything other than what is in the .vmx configuration file,

all inbound frames are dropped.

 

In Forget Transmits – Any outbound frame with a source MAC address that is different from the

one currently set on the adapter are dropped.

 

Traffic Shaping Policy

 

A traffic shaping policy is defined by average bandwidth, peak bandwidth, and burst size.

You can establish a traffic shaping policy for each port group and each distributed port or distributed port group.

 

ESXi shapes outbound network traffic on standard switches and inbound and outbound traffic on distributed switches.

 Traffic shaping restricts the network bandwidth available on a port, but can also be configured to

allow bursts of traffic to flow through at higher speeds.

 

 

 

 

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The Status policy here is applied to each virtual adapter attached to the port group, not to the standard switch

as a whole. If you enable the policy exception in the Status field, you set limits on the amount of networking

bandwidth allocation for each virtual adapter associated with this particular port group. If you disable the

policy, services have a clear connection to the physical network by default.