Administrator Guide

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.
Multi-Process OSPFv2 (IPv4 only)
Multi-process OSPF is supported on the Z9000 platform with Dell Networking OS version 7.8.1.0 and later, and is supported on
OSPFv2 with IPv4 only.
Multi-process OSPF allows multiple OSPFv2 processes on a single router. Multiple OSPFv2 processes allow for isolating
routing domains, supporting multiple route policies and priorities in different domains, and creating smaller domains for easier
management.
The Z9000 supports up to 32 OSPFv2 processes.
Each OSPFv2 process has a unique process ID and must have an associated router ID. There must be an equal number of
interfaces and must be in Layer-3 mode for the number of processes created. For example, if you create five OSPFv2 processes
on a system, there must be at least five interfaces assigned in Layer 3 mode.
Each OSPFv2 process is independent. If one process loses adjacency, the other processes continue to function.
Processing SNMP and Sending SNMP Traps
Though there are may be several OSPFv2 processes, only one process can process simple network management protocol
(SNMP) requests and send SNMP traps.
NOTE: SNMP get request corresponding to the OspfNbrOption feild in the OspfNbrTable returns a value of 66.
RFC-2328 Compliant OSPF Flooding
In OSPF, flooding is the most resource-consuming task. The flooding algorithm described in RFC 2328 requires that OSPF flood
LSAs on all interfaces, as governed by LSA’s flooding scope (refer to Section 13 of the RFC.)
When multiple direct links connect two routers, the RFC 2328 flooding algorithm generates significant redundant information
across all links.
By default, Dell Networking OS implements an enhanced flooding procedure which dynamically and intelligently detects when to
optimize flooding. Wherever possible, the OSPF task attempts to reduce flooding overhead by selectively flooding on a subset of
the interfaces between two routers.
Enabling RFC-2328 Compliant OSPF Flooding
To enable OSPF flooding, use the following command.
When you enable this command, it configures Dell Networking OS to flood LSAs on all interfaces.
● Enable RFC 2328 flooding.
ROUTER OSPF mode
flood-2328
To confirm RFC 2328 flooding behavior, use the debug ip ospf packet command. The following example shows no change
in the updated packets (shown in bold).
ACKs 2 (shown in bold) is printed only for ACK packets.
00:10:41 : OSPF(1000:00):
Rcv. v:2 t:5(LSAck) l:64 Acks 2 rid:2.2.2.2
aid:1500 chk:0xdbee aut:0 auk: keyid:0 from:Vl 1000
LSType:Type-5 AS External id:160.1.1.0 adv:6.1.0.0 seq:0x8000000c
LSType:Type-5 AS External id:160.1.2.0 adv:6.1.0.0 seq:0x8000000c
00:10:41 : OSPF(1000:00):
Rcv. v:2 t:5(LSAck) l:64 Acks 2 rid:2.2.2.2
aid:1500 chk:0xdbee aut:0 auk: keyid:0 from:Vl 100
LSType:Type-5 AS External id:160.1.1.0 adv:6.1.0.0 seq:0x8000000c
LSType:Type-5 AS External id:160.1.2.0 adv:6.1.0.0 seq:0x8000000c
00:10:41 : OSPF(1000:00):
468
Open Shortest Path First (OSPFv2 and OSPFv3)