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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 different 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 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
Only the process in default vrf can process the SNMP requests and send SNMP traps.
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.
If RFC 2328 flooding behavior is required, enable it by using the command flood-2328 in ROUTER OSPF mode. When enabled,
this command configures Dell Networking OS to flood LSAs on all interfaces.
Confirm RFC 2328 flooding 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
To confirm that RFC-2328 compliant OSPF flooding is enabled, use the show ip ospf command.
Example of the show ip ospf Command
Dell#show ip ospf
Routing Process ospf 1 with ID 2.2.2.2
Supports only single TOS (TOS0) routes
It is an Autonomous System Boundary Router
It is Flooding according to RFC 2328
SPF schedule delay 5 secs, Hold time between two SPFs 10 secs
Open Shortest Path First (OSPFv2)
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