Reference Guide
Open Shortest Path First (OSPFv2 and OSPFv3) | 641
OSPF ACK Packing
The OSPF ACK Packing feature bundles multiple LS acknowledgments in a single packet, significantly
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 is non-configurable.
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 FTOS, the OSPF dead interval value is, by default, set to 40 seconds, and is independent of the OSPF
hello interval. Configuring a hello interval does not change the dead interval in FTOS. 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 as well.
For more information regarding this functionality or for assistance, go to
www.force10networks.com/
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 configuration.
INTERFACE mode
ip ospf dead-interval <x>
In the following example, the dead interval is set at four times (4x) the hello interval (shown in bold).
Figure 34-6. Example of Setting a Dead Interval
Figure 34-7. Example of Viewing a Dead Interval Setting
FTOS(conf)#int tengig- 2/2
FTOS(conf-if-te-2/2)#ip ospf hello-interval 20
FTOS(conf-if-te-2/2)#ip ospf dead-interval 80
FTOS(conf-if-te-2/2)#
FTOS (conf-if-te-2/2)#ip ospf dead-interval 20
FTOS (conf-if-te-2/2)#do show ip os int tengig 1/3
TenGigabitEthernet 2/2 is up, line protocol is up
Internet Address 20.0.0.1/24, Area 0
Process ID 10, Router ID 1.1.1.2, Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 1.1.1.2, Interface address 30.0.0.1
Backup Designated Router (ID) 1.1.1.1, Interface address 30.0.0.2
Timer intervals configured, Hello 20, Dead 80, Wait 20, Retransmit 5
Hello due in 00:00:04
Neighbor Count is 1, Adjacent neighbor count is 1
Adjacent with neighbor 1.1.1.1 (Backup Designated Router)