Deployment Guide
Fast Convergence (OSPFv2, IPv4 Only)
Fast convergence allows you to dene the speeds at which LSAs are originated and accepted, and reduce OSPFv2 end-to-end
convergence time.
The Dell Networking OS allows you to accept and originate LSAa as soon as they are available to speed up route information propagation.
NOTE: The faster the convergence, the more frequent the route calculations and updates. This impacts CPU utilization and may
impact adjacency stability in larger topologies.
Processing SNMP and Sending SNMP Traps
Only the process in default vrf can process the SNMP requests and send SNMP traps.
OSPF ACK Packing
The OSPF ACK packing feature bundles multiple LS acknowledgements in a single packet, signicantly reducing the number of ACK
packets transmitted when the number of LSAs increases.
This feature also enhances network utilization and reduces the number of small ACK packets sent to a neighboring router. OSPF ACK
packing is enabled by default and non-congurable.
Setting OSPF Adjacency with Cisco Routers
To establish an OSPF adjacency between Dell Networking and Cisco routers, the hello interval and dead interval must be the same on both
routers.
In Dell Networking OS, the OSPF dead interval value is, by default, set to 40 seconds, and is independent of the OSPF hello interval.
Conguring a hello interval does not change the dead interval in Dell. In contrast, the OSPF dead interval on a Cisco router is, by default,
four times as long as the hello interval. Changing the hello interval on the Cisco router automatically changes the dead interval.
For more information regarding this functionality or for assistance, go to http://www.dell.com/support/my-support/.
To ensure equal intervals between the routers, use the following command.
• Manually set the dead interval of the Dell Networking router to match the Cisco conguration.
INTERFACE mode
ip ospf dead-interval <x>
Example of Setting a Dead Interval
Example of Viewing Dead Interval Setting
In the following example, the dead interval is set at 4x the hello interval (shown in bold).
Dell(conf)#int tengig 2/2
Dell(conf-if-te-2/2)#ip ospf hello-interval 20
Dell(conf-if-te-2/2)#ip ospf dead-interval 80
Dell(conf-if-te-2/2)#
In the following example, the dead interval is set at 4x the hello interval (shown in bold).
Dell (conf-if-te-2/2)#ip ospf dead-interval 20
Dell (conf-if-te-2/2)#do show ip os int tengig 1/3
TenGigabitEthernet 2/2 is up, line protocol is up
Open Shortest Path First (OSPFv2 and OSPFv3)
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