OSPF-5類LSA和4類LSA
阿新 • • 發佈：2017-11-25
ospf 5類lsa 4類lsa # 5類LSA ：外部路由前綴 + ASBR的router_id
IOU5#sh ip ospf data ext
OSPF Router with ID (5.5.5.5) (Process ID 1)
Type-5 AS External Link States
LS age: 71
Options: (No TOS-capability, DC, Upward)
LS Type: AS External Link
Link State ID: 10.1.55.0 (External Network Number )
Advertising Router: 5.5.5.5
LS Seq Number: 80000002
Checksum: 0x61E7
Length: 36
Network Mask: /24
Metric Type: 2 (Larger than any link state path)
MTID: 0
Metric: 20 # 種子metric
Forward Address: 0.0.0.0
External Route Tag: 0
# 區域內路由OE T5 + T1/T2
IOU4# sh ip ospf data
OSPF Router with ID (4.4.4.4) (Process ID 1)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
2.2.2.2 2.2.2.2 1 (DNA) 0x80000005 0x00EBE8 1
3.3.3.3 3.3.3.3 1 (DNA) 0x80000005 0x00AD1E 1
4.4.4.4 4.4.4.4 294 0x80000006 0x00F05A 4
5.5.5.5 5.5.5.5 211 0x80000004 0x006863 3
Type-5 AS External Link States
Link ID ADV Router Age Seq# Checksum Tag
10.1.55.0 5.5.5.5 211 0x80000003 0x005FE8 0
IOU4#sh ip ro 10.1.55.55
Routing entry for 10.1.55.0/24
Known via "ospf 1", distance 110, metric 20, type extern 2, forward metric 64
Last update from 10.1.45.5 on Serial2/1, 01:15:51 ago
Routing Descriptor Blocks:
* 10.1.45.5, from 5.5.5.5, 01:15:51 ago, via Serial2/1
Route metric is 20, traffic share count is 1
# 4類LSA： ASBR的router_id + 本區域ABR的router_id
IOU1#sh ip ospf da asbr-summary
OSPF Router with ID (1.1.1.1) (Process ID 1)
Summary ASB Link States (Area 2)
Routing Bit Set on this LSA in topology Base with MTID 0
LS age: 840
Options: (No TOS-capability, DC, Upward)
LS Type: Summary Links(AS Boundary Router)
Link State ID: 5.5.5.5 (AS Boundary Router address)
Advertising Router: 2.2.2.2
LS Seq Number: 80000003
Checksum: 0x5944
Length: 28
Network Mask: /0
MTID: 0 Metric: 128
Routing Bit Set on this LSA in topology Base with MTID 0
LS age: 814
Options: (No TOS-capability, DC, Upward)
LS Type: Summary Links(AS Boundary Router)
Link State ID: 5.5.5.5 (AS Boundary Router address)
Advertising Router: 3.3.3.3
LS Seq Number: 80000003
Checksum: 0x3B5E
Length: 28
Network Mask: /0
MTID: 0 Metric: 128
# 域間路由： T5 + T4 + T1/T2
IOU1#sh ip ospf da
OSPF Router with ID (1.1.1.1) (Process ID 1)
Router Link States (Area 2)
Link ID ADV Router Age Seq# Checksum Link count
1.1.1.1 1.1.1.1 751 0x80000004 0x00E906 2
2.2.2.2 2.2.2.2 783 0x80000007 0x008C74 1
3.3.3.3 3.3.3.3 756 0x80000007 0x004EA9 1
Summary ASB Link States (Area 2)
Link ID ADV Router Age Seq# Checksum
5.5.5.5 2.2.2.2 783 0x80000003 0x005944
5.5.5.5 3.3.3.3 756 0x80000003 0x003B5E
Type-5 AS External Link States
Link ID ADV Router Age Seq# Checksum Tag
10.1.55.0 5.5.5.5 727 0x80000003 0x005FE8 0# 5類LSA的外部路由OE2選擇：
# 1、外部路由的metric小優先
IOU1(config-router)#redistribute connected route-map loop metric 10
IOU4# sh ip ro
O E2 10.1.55.0/24 [110/10] via 10.1.234.3, 00:00:03, Serial2/0
[110/10] via 10.1.234.2, 00:00:03, Serial2/0
IOU4#sh ip ro 10.1.55.55
Routing entry for 10.1.55.0/24
Known via "ospf 1", distance 110, metric 10, type extern 2, forward metric 74
Last update from 10.1.234.2 on Serial2/0, 00:04:44 ago
Routing Descriptor Blocks:
* 10.1.234.3, from 1.1.1.1, 00:04:44 ago, via Serial2/0
Route metric is 10, traffic share count is 1
10.1.234.2, from 1.1.1.1, 00:04:44 ago, via Serial2/0
Route metric is 10, traffic share count is 1
# 2、外部路由的metric相等，forward metric小優先；
IOU1(config-router)#redistribute connected route-map loop metric 20
IOU4# sh ip roOSPF-5類LSA和4類LSA