OSPF – базовая настройка мультизонной структуры
Router(config)#router ospf 1 Router(config-router)#network 192.168.1.0 0.0.0.255 area 0 Router(config-router)#network 10.0.1.0 0.0.0.255 area 0
Router(config)#router ospf 1 Router(config-router)#network 192.168.3.0 0.0.0.255 area 0 Router(config-router)#network 10.0.1.0 0.0.0.255 area 0
Router(config)#router ospf 1 Router(config-router)#network 192.168.2.0 0.0.0.255 area 0 Router(config-router)#network 10.0.1.0 0.0.0.255 area 0
Настройка ABR (пограничного) роутера
ABR(config)#router ospf 1 ABR(config-router)#netw ABR(config-router)#network 10.0.1.0 0.0.0.255 area 0 ABR(config-router)# 00:31:26: %OSPF-5-ADJCHG: Process 1, Nbr 192.168.2.1 on GigabitEthernet0/0 from LOADING to FULL, Loading Done 00:31:26: %OSPF-5-ADJCHG: Process 1, Nbr 192.168.3.1 on GigabitEthernet0/0 from LOADING to FULL, Loading Done ABR(config-router)#network 10.0.2.0 0.0.0.255 area 1
Посмотреть DR роутер
Router#sh ip ospf nei Neighbor ID Pri State Dead Time Address Interface 192.168.1.1 1 FULL/DROTHER 00:00:32 10.0.1.1 GigabitEthernet0/0 192.168.3.1 1 FULL/DR 00:00:31 10.0.1.3 GigabitEthernet0/0 10.0.2.1 1 FULL/DROTHER 00:00:38 10.0.1.4 GigabitEthernet0/0 Router#
Назначить приоритет
ABR(config-if)#ip ospf priority 100 ABR(config-if)#int g1/0 ABR(config-if)#ip ospf priority 100
Перезагрузить OSPF
ABR#clear ip ospf process Reset ALL OSPF processes? [no]: y
Это нужно сделать на всех роутерах.
Смотрим что получилось
Router#sh ip ospf nei Neighbor ID Pri State Dead Time Address Interface 192.168.1.1 1 FULL/DROTHER 00:00:33 10.0.1.1 GigabitEthernet0/0 192.168.3.1 1 FULL/DROTHER 00:00:32 10.0.1.3 GigabitEthernet0/0 10.0.2.1 100 FULL/DR 00:00:39 10.0.1.4 GigabitEthernet0/0
Router#sh ip rou Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2 E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area * - candidate default, U - per-user static route, o - ODR P - periodic downloaded static route Gateway of last resort is not set 10.0.0.0/24 is subnetted, 2 subnets C 10.0.1.0 is directly connected, GigabitEthernet0/0 O IA 10.0.2.0 [110/2] via 10.0.1.4, 00:04:24, GigabitEthernet0/0 172.20.0.0/24 is subnetted, 3 subnets O IA 172.20.1.0 [110/3] via 10.0.1.4, 00:04:24, GigabitEthernet0/0 O IA 172.20.2.0 [110/3] via 10.0.1.4, 00:04:24, GigabitEthernet0/0 O IA 172.20.3.0 [110/3] via 10.0.1.4, 00:04:24, GigabitEthernet0/0 O 192.168.1.0/24 [110/2] via 10.0.1.1, 00:04:14, GigabitEthernet0/0 C 192.168.2.0/24 is directly connected, GigabitEthernet2/0 O 192.168.3.0/24 [110/2] via 10.0.1.3, 00:56:34, GigabitEthernet0/0 * IA означает, что маршруты OSPF зародились в другом регионе
Router#sh ip ospf nei Neighbor ID Pri State Dead Time Address Interface 10.0.2.1 100 FULL/DR 00:00:31 10.0.1.4 GigabitEthernet0/0 192.168.3.1 1 FULL/DROTHER 00:00:34 10.0.1.3 GigabitEthernet0/0 192.168.1.1 1 FULL/DROTHER 00:00:34 10.0.1.1 GigabitEthernet0/0 Router#
Neighbor ID – 32-х битное число, которое, роутер назначает сам, вибирая наибольший IP-адресс из своих интерфейсов.
Это поведение можно изменить. Хорошим тоном считается DR назначить наибольший ID
ABR(config)#router ospf 1 ABR(config-router)#router-id 20.20.20.20 ABR(config-router)#Reload or use "clear ip ospf process" command, for this to take effect
После этого нужно опять перегрузить OSPF
ABR#clear ip ospf process Reset ALL OSPF processes? [no]: y Router#sh ip ospf ne Neighbor ID Pri State Dead Time Address Interface 5.5.5.5 1 2WAY/DROTHER 00:00:39 10.0.2.3 GigabitEthernet0/0 20.20.20.20 100 FULL/DR 00:00:34 10.0.2.1 GigabitEthernet0/0 6.6.6.6 1 FULL/BDR 00:00:31 10.0.2.2 GigabitEthernet0/0 * BDR - запасной DR ** DROTHER - эти ни DR ни BDR, если упадут DR & BDR, то произойдут выборы *** FULL - полное взаимодействие *** 2WAY - просто соседские отношения, без обмена LSA, эти роутеры обмениваются LSA только с DR и BDR
Если роутеру установить приоритет 0 то он не будет вибираться ни DR ни BDR.
Router#sh ip ospf database OSPF Router with ID (1.1.1.1) (Process ID 1) Router Link States (Area 0) Link ID ADV Router Age Seq# Checksum Link count | 20.20.20.20 20.20.20.20 1139 0x80000003 0x002073 1 | 3.3.3.3 3.3.3.3 1139 0x80000004 0x006639 2 | -- LSA первого типа 1.1.1.1 1.1.1.1 1134 0x80000004 0x00b8fa 2 | 2.2.2.2 2.2.2.2 1134 0x80000004 0x008f1a 2 | Net Link States (Area 0) Link ID ADV Router Age Seq# Checksum | 10.0.1.4 20.20.20.20 1134 0x80000003 0x00328d | -- LSA второго типа Summary Net Link States (Area 0) Link ID ADV Router Age Seq# Checksum 10.0.2.0 20.20.20.20 1175 0x80000001 0x00a061 | 10.0.3.0 20.20.20.20 1170 0x80000002 0x00946b | 172.20.1.0 20.20.20.20 1124 0x80000003 0x007eca | 172.20.3.0 20.20.20.20 1124 0x80000004 0x0066df | 172.20.2.0 20.20.20.20 1124 0x80000005 0x006fd6 | -- LSA третьего типа 172.16.1.0 20.20.20.20 1119 0x80000006 0x00a8a1 | 172.16.3.0 20.20.20.20 1119 0x80000007 0x0090b6 | 172.16.2.0 20.20.20.20 1119 0x80000008 0x0099ad | Router#
Router#sh ip rout ospf 1 10.0.0.0/24 is subnetted, 3 subnets O IA 10.0.2.0 [110/2] via 10.0.1.4, 00:22:58, GigabitEthernet0/0 O IA 10.0.3.0 [110/2] via 10.0.1.4, 00:22:58, GigabitEthernet0/0 172.16.0.0/24 is subnetted, 3 subnets O IA 172.16.1.0 [110/3] via 10.0.1.4, 00:22:48, GigabitEthernet0/0 O IA 172.16.2.0 [110/3] via 10.0.1.4, 00:22:48, GigabitEthernet0/0 O IA 172.16.3.0 [110/3] via 10.0.1.4, 00:22:48, GigabitEthernet0/0 172.20.0.0/24 is subnetted, 3 subnets O IA 172.20.1.0 [110/3] via 10.0.1.4, 00:22:58, GigabitEthernet0/0 | O IA 172.20.2.0 [110/3] via 10.0.1.4, 00:22:58, GigabitEthernet0/0 | -- маршруты полученные по LSA 3 типа O IA 172.20.3.0 [110/3] via 10.0.1.4, 00:22:58, GigabitEthernet0/0 | O 192.168.2.0 [110/2] via 10.0.1.2, 00:22:58, GigabitEthernet0/0 | O 192.168.3.0 [110/2] via 10.0.1.3, 00:22:58, GigabitEthernet0/0 | -- информация о маршрутах в нашем регионе по LSA первого типа
Посмотреть информацию о LSA
Router#sh ip ospf database router OSPF Router with ID (1.1.1.1) (Process ID 1) Router Link States (Area 0) LS age: 181 Options: (No TOS-capability, DC) LS Type: Router Links Link State ID: 1.1.1.1 Advertising Router: 1.1.1.1 LS Seq Number: 80000005 Checksum: 0xb6fb Length: 48 Number of Links: 2 Link connected to: a Transit Network (Link ID) Designated Router address: 10.0.1.4 (Link Data) Router Interface address: 10.0.1.1 Number of TOS metrics: 0 TOS 0 Metrics: 1 Link connected to: a Stub Network (Link ID) Network/subnet number: 192.168.1.0 (Link Data) Network Mask: 255.255.255.0 Number of TOS metrics: 0 TOS 0 Metrics: 1 LS age: 187 --More--
Router#sh ip osp Routing Process "ospf 1" with ID 1.1.1.1 Supports only single TOS(TOS0) routes Supports opaque LSA SPF schedule delay 5 secs, Hold time between two SPFs 10 secs Minimum LSA interval 5 secs. Minimum LSA arrival 1 secs Number of external LSA 0. Checksum Sum 0x000000 Number of opaque AS LSA 0. Checksum Sum 0x000000 Number of DCbitless external and opaque AS LSA 0 Number of DoNotAge external and opaque AS LSA 0 Number of areas in this router is 1. 1 normal 0 stub 0 nssa External flood list length 0 Area BACKBONE(0) Number of interfaces in this area is 2 Area has no authentication SPF algorithm executed 17 times | -- сколько раз делался перерасчет Area ranges are Number of LSA 13. Checksum Sum 0x05c771 Number of opaque link LSA 0. Checksum Sum 0x000000 Number of DCbitless LSA 0 Number of indication LSA 0 Number of DoNotAge LSA 0 Flood list length 0 --More--
Изменим схему сети, что бы посмотреть балансировку
Посмотреть стоимость маршрута
ABR#sh ip ospf int f4/0 FastEthernet4/0 is up, line protocol is up Internet address is 20.0.1.2/24, Area 0 Process ID 1, Router ID 20.20.20.20, Network Type BROADCAST, Cost: 1 | -- стоимость Transmit Delay is 1 sec, State DR, Priority 100 Designated Router (ID) 20.20.20.20, Interface address 20.0.1.2 Backup Designated Router (ID) 10.10.10.10, Interface address 20.0.1.1 Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5 Hello due in 00:00:04 Index 2/2, flood queue length 0 Next 0x0(0)/0x0(0) Last flood scan length is 1, maximum is 1 Last flood scan time is 0 msec, maximum is 0 msec Neighbor Count is 1, Adjacent neighbor count is 1 Adjacent with neighbor 10.10.10.10 (Backup Designated Router) Suppress hello for 0 neighbor(s)
Посмотреть скорость интерфейса
ABR#sh int f4/0
FastEthernet4/0 is up, line protocol is up (connected)
Hardware is Lance, address is 0060.2f0a.8bed (bia 0060.2f0a.8bed)
Internet address is 20.0.1.2/24
MTU 1500 bytes, BW 100000 Kbit, DLY 100 usec, | -- скорость интерф.
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
ARP type: ARPA, ARP Timeout 04:00:00,
Last input 00:00:08, output 00:00:05, output hang never
Last clearing of "show interface" counters never
Input queue: 0/75/0 (size/max/drops); Total output drops: 0
Queueing strategy: fifo
Output queue :0/40 (size/max)
5 minute input rate 54 bits/sec, 0 packets/sec
5 minute output rate 54 bits/sec, 0 packets/sec
760 packets input, 62204 bytes, 0 no buffer
Received 0 broadcasts, 0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort
0 input packets with dribble condition detected
574 packets output, 46216 bytes, 0 underruns
0 output errors, 0 collisions, 1 interface resets
0 babbles, 0 late collision, 0 deferred
0 lost carrier, 0 no carrier
--More--
Можно поменять стоимость интерфейса вручную, при этом он уже не будет просчитываться роутером автоматически по формуле
Router(config)#int f0/0 Router(config-if)#ip ospf cost 10
Посмотреть метрику
Router#sh ip rout
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
10.0.0.0/24 is subnetted, 3 subnets
C 10.0.1.0 is directly connected, FastEthernet0/0
O IA 10.0.2.0 [110/2] via 20.0.1.2, 00:43:46, FastEthernet1/0
O IA 10.0.3.0 [110/2] via 20.0.1.2, 00:43:46, FastEthernet1/0
20.0.0.0/24 is subnetted, 2 subnets
C 20.0.1.0 is directly connected, FastEthernet1/0
O 20.0.2.0 [110/2] via 20.0.1.2, 00:27:01, FastEthernet1/0
[110/2] via 10.0.1.5, 00:27:01, FastEthernet0/0
172.16.0.0/24 is subnetted, 3 subnets
O IA 172.16.1.0 [110/3] via 20.0.1.2, 00:43:46, FastEthernet1/0 | -- метрика
O IA 172.16.2.0 [110/3] via 20.0.1.2, 00:43:46, FastEthernet1/0
O IA 172.16.3.0 [110/3] via 20.0.1.2, 00:43:46, FastEthernet1/0
172.20.0.0/24 is subnetted, 3 subnets
O IA 172.20.1.0 [110/3] via 20.0.1.2, 00:43:46, FastEthernet1/0
O IA 172.20.2.0 [110/3] via 20.0.1.2, 00:43:46, FastEthernet1/0
O IA 172.20.3.0 [110/3] via 20.0.1.2, 00:43:46, FastEthernet1/0
O 192.168.1.0/24 [110/2] via 10.0.1.1, 00:26:46, FastEthernet0/0
O 192.168.2.0/24 [110/2] via 10.0.1.2, 00:26:46, FastEthernet0/0
O 192.168.3.0/24 [110/2] via 10.0.1.3, 00:26:46, FastEthernet0/0