Users 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 S5000 switch for 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 dierent domains, and creating smaller domains for easier management.
The S5000 support up to 16 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 ve OSPFv2 processes on a system,
there must be at least ve 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 may be several OSPFv2 processes, only one process can process simple network management protocol (SNMP)
requests and send SNMP traps.
The mib-binding command identies one of the OSPVFv2 processes as the process responsible for SNMP management. If you
do not specify the mib-binding command, the rst OSPFv2 process created manages the SNMP processes and traps.
RFC-2328 Compliant OSPF Flooding
In OSPF, ooding is the most resource-consuming task. The ooding algorithm described in RFC 2328 requires that OSPF ood
LSAs on all interfaces, as governed by LSA’s ooding scope (refer to Section 13 of the RFC.)
When multiple direct links connect two routers, the RFC 2328 ooding algorithm generates signicant redundant information across
all links.
By default, Dell Networking OS implements an enhanced ooding procedure which dynamically and intelligently detects when to
optimize ooding. Wherever possible, the OSPF task attempts to reduce ooding overhead by selectively ooding on a subset of the
interfaces between two routers.
If RFC 2328 ooding behavior is required, enable it by using the command ood-2328 in ROUTER OSPF mode. When enabled, this
command congures Dell Networking OS to ood LSAs on all interfaces.
Conrm RFC 2328 ooding behavior by using the debug ip ospf packet command and look for output similar to the following:
Enabling RFC-2328–Compliant OSPF Flooding
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):
Rcv. v:2 t:4(LSUpd) l:100 rid:6.1.0.0
aid:0 chk:0xccbd aut:0 auk: keyid:0 from:Te 10/21
Number of LSA:2
LSType:Type-5 AS External(5) Age:1 Seq:0x8000000c id:170.1.1.0 Adv:6.1.0.0
Netmask:255.255.255.0 fwd:0.0.0.0 E2, tos:0 metric:0
LSType:Type-5 AS External(5) Age:1 Seq:0x8000000c id:170.1.2.0 Adv:6.1.0.0
Netmask:255.255.255.0 fwd:0.0.0.0 E2, tos:0 metric:0
Open Shortest Path First (OSPFv2)
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