Fast Convergence After Mstp Topology Changes; Egress Interface Selection (Eis) For Http And Igmp Applications - Dell Z9000 Configuration Manual

ip igmp snooping last-member-query-interval

Fast Convergence after MSTP Topology Changes

The following describes the fast convergence feature.
When a port transitions to the Forwarding state as a result of an STP or MSTP topology change, Dell
Networking OS sends a general query out of all ports except the multicast router ports. The host sends a
response to the general query and the forwarding database is updated without having to wait for the
query interval to expire.
When an IGMP snooping switch is not acting as a querier, it sends out the general query in response to
the MSTP triggered link-layer topology change, with the source IP address of 0.0.0.0 to avoid triggering
querier election.
Egress Interface Selection (EIS) for HTTP and IGMP
Applications
You can use the Egress Interface Selection (EIS) feature to isolate the management and front-end port
domains for HTTP and IGMP traffic. Also, EIS enables you to configure the responses to switch-destined
traffic by using the management port IP address as the source IP address. This information is sent out of
the switch through the management port instead of the front-end port.
The management EIS feature is applicable only for the out-of-band (OOB) management port. References
in this section to the management default route or static route denote the routes configured using the
management route command. The management default route can be either configured statically or
returned dynamically by the DHCP client. A static route points to the management interface or a
forwarding router.
Transit traffic (destination IP not configured in the switch) that is received on the front-end port with
destination on the management port is dropped and received in the management port with destination
on the front-end port is dropped.
Switch-destined traffic (destination IP configured in the switch) is:
• Received in the front-end port with destination IP equal to management port IP address or
management port subnet broadcast address is dropped.
• Received in the management port with destination IP not equal to management IP address or
management subnet broadcast address is dropped.
Traffic (switch initiated management traffic or responses to switch-destined traffic with management port
IP address as the source IP address) for user-specified management protocols must exit out of the
management port. In this chapter, all the references to traffic indicate switch-initiated traffic and
responses to switch-destined traffic with management port IP address as the source IP address.
In customer deployment topologies, it might be required that the traffic for certain management
applications needs to exit out of the management port only. You can use EIS to control and the traffic
can exit out of any port based on the route lookup in the IP stack.
One typical example is an SSH session to an unknown destination or an SSH connection that is destined
to the management port IP address. The management default route can coexist with front-end default
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Internet Group Management Protocol (IGMP)