Users Guide
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
Example of the show ip ospf Command
To confirm that RFC-2328 compliant OSPF flooding is enabled, use 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
Number of area in this router is 1, normal 0 stub 0 nssa 1
--More--
Open Shortest Path First (OSPFv2) 740










