Service Manual

Trac type /
Application type
Switch initiated trac Switch-destined trac Transit Trac
management port is down or route lookup
fails, packets are dropped
Non-EIS
management
application
Front-end default route will take
higher precedence over
management default route and
SSH session to an unknown
destination uses the front-end
default route only. No change in
the existing behavior.
If source TCP/UDP port matches a
management application and the source IP
address is a management port IP address, the
management port is the preferred egress port
selected based on route lookup in EIS table. If
the management port is down or the route
lookup fails, packets are dropped
Trac from
management port to
data port and from data
port to management
port is blocked
• EIS is enabled implies that EIS feature is enabled and the application might or might not be congured as a management
application
• EIS is disabled implies that either EIS feature itself is disabled or that the application is not congured as a management
application
Transit Trac
This phenomenon occurs where trac is transiting the switch. Trac has not originated from the switch and is not terminating on
the switch.
• Drop the packets that are received on the front-end data port with destination on the management port.
• Drop the packets that received on the management port with destination as the front-end data port.
Switch-Destined Trac
This phenomenon occurs where trac is terminated on the switch. Trac has not originated from the switch and is not transiting
the switch.
The switch accepts all trac destined to the switch, which is received on management or front-end data port. Response trac with
management port IP address as source IP address is handled in the same manner as switch originated trac.
Switch-Originated Trac
This phenomenon occurs where trac is originating from the switch.
1. Management Applications (Applications that are congured as management applications):
The management port is an egress port for management applications. If the management port is down or the destination is not
reachable through the management port (next hop ARP is not resolved, and so on), and if the destination is reachable through
a data port, then the management application trac is sent out through the front-end data port. This fallback mechanism is
required.
2. Non-Management Applications (Applications that are not congured as management applications as dened by this feature):
Non-management application trac exits out of either front-end data port or management port based on routing table. If there
is a default route on both the management and front-end data port, the default for the data port is preferred route.
Behavior of Various Applications for Switch-Initiated Trac
This section describes the dierent system behaviors that occur when trac is originating from the switch:
EIS Behavior: If the destination TCP/UDP port matches a congured management application, a route lookup is done in the EIS
table and the management port gets selected as the egress port. If management port is down or the route lookup fails, packets are
dropped.
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Internet Group Management Protocol (IGMP)