There is a limit of 512 total active and passive interfaces, but only a total of 128 can be active interfaces.
About configuring shortest path first (SPF) scheduling
SPF scheduling (throttling) can be configured in intervals of seconds to potentially delay SPF calculations when
the network is unstable or there is a change in topology. It provides a granularity of one to four seconds between
SPF calculations as opposed to the current default of five seconds.
The interval for the SPF calculations is dynamically chosen, based on the frequency of topology changes in the
network. The chosen interval is within user-specified ranges of values. When the network topology is unstable,
SPF throttling calculates SPF scheduling intervals that are longer, until the topology is again stable.
NOTE:
It is guaranteed that no SPF will be calculated within the SPF currently in effect, however, it is not
guaranteed that the SPF will be calculated at the exact expiration of the timer if there have been
updates. The timer may be delayed due to system constraints.
Graceful shutdown of OSPF routing
OSPF routing can be gracefully shut down on switches without losing packets that are in transit. OSPF neighbors
are informed that the router should not be used for forwarding traffic, which allows for maintenance on the switch
without interrupting traffic in the network. There is no effect on the saved switch configuration
Prior to a switch shutdown, the CLI/SNMP
reload
command or the CLI
boot
command is executed to initiate
the sending of OSPF "empty hello list" messages on the interfaces that are part of the OSPF routing
configuration. After a small delay (approximately 2 seconds) that allows the messages to be transmitted on all
applicable interfaces, the
boot
or
reload
command continues.
Modules operating in nonstop mode
When a switch is in standalone mode and OSPF routing is enabled, the "empty hello list" is transmitted whenever
the
boot
or
reload
commands are executed.
When the switch is operating in nonstop switching mode (redundant) and a single module is being reloaded or
booted, the standby module will notify neighboring switches of the management module failover. If the failover
fails, the "empty hello list" is transmitted before the switch is rebooted.
When a switch is operating with multiple management modules in warm standby mode, the "empty hello list" is
sent when a
reload
or
boot
command is executed. The standby management module sends out OSPF hello
packets after becoming the active management module.
OSPF equal-cost multipath (ECMP) for different subnets available through
the same next-hop routes
The switches support optional load-sharing across redundant links where the network offers two, three, or four
equal-cost next-hop routes for traffic to different subnets. (All traffic for different hosts in the same subnet goes
through the same next-hop router.)
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Aruba 3810 / 5400R Multicast and Routing Guide for ArubaOS-
Switch 16.08
