Difference between revisions of "Cisco OSPF"

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Line 31: Line 31:
 
  router ospf [process-id]
 
  router ospf [process-id]
  
router-id for this OSPF process (in IP address format)
+
router-id for this OSPF process (in IPv4 address format)
 
  router-id [OSPF router-id]  
 
  router-id [OSPF router-id]  
 
  log-adjacency-changes
 
  log-adjacency-changes
 +
 +
Uppdatera reference bandwidth till 100G
 +
router ospf 1
 +
auto-cost reference-bandwidth 100000
 +
exit
  
 
Enable routing on an IP network
 
Enable routing on an IP network
Line 59: Line 64:
 
  exit
 
  exit
  
ABR Summarization
+
===Summarization===
 +
'''ABR'''
 
  router ospf 1
 
  router ospf 1
 
  area 10 range 10.10.0.0 255.255.252.0
 
  area 10 range 10.10.0.0 255.255.252.0
 
  exit
 
  exit
  
ASBR Summarization
+
'''ASBR'''
 
  router ospf 1
 
  router ospf 1
 
  summary-address 10.10.0.0 255.255.252.0
 
  summary-address 10.10.0.0 255.255.252.0
 
  exit
 
  exit
  
Uppdatera reference bandwidth till 100G
+
===Tuning protocol parameters===
 +
ip ospf hello-interval ''seconds''
 +
ip ospf dead-interval ''seconds''
 +
ip ospf retransmission-interval ''seconds''
 +
ip ospf transmit-delay ''seconds''
 +
 
 +
===Stub===
 +
No LSA type 5
 +
area 1 stub
 +
''Stub bit is sent in hello packets''
 +
 
 +
===Totally Stubby===
 +
No LSA type 3,4,5. Default route only.<br/>
 +
ABR
 +
area 1 stub no-summary
 +
Others
 +
area 1 stub
 +
 
 +
===NSSA===
 +
LSA type 7
 +
area 1 nssa
 +
 
 +
===NSSA Totally Stubby===
 +
LSA type 7. No LSA type 3,4.
 +
area 1 nssa no-summary
 +
 
 +
==Virtual Link==
 +
Virtual link är rekommenderat som backup- eller temporär anslutning.
 +
 
 +
'''R1'''
 +
router ospf 1
 +
network 10.0.1.0 0.0.0.255 area 1
 +
network 1.1.1.0 0.0.0.255 area 0
 +
area 1 virtual-link 3.3.3.3  #Router-ID
 +
 
 +
'''R3'''
 
  router ospf 1
 
  router ospf 1
  auto-cost reference-bandwidth 100000
+
  network 10.0.1.0 0.0.0.255 area 1
  exit
+
network 10.0.2.0 0.0.0.255 area 2
 +
network 3.3.3.0 0.0.0.255 area 2
 +
area 1 virtual-link 1.1.1.1  #Router-ID
 +
 
 +
'''Show'''
 +
  show ip ospf virtual-links
  
 +
===Diverse===
 
'''Loopback'''  
 
'''Loopback'''  
 
  ip ospf network point-to-point
 
  ip ospf network point-to-point
Line 86: Line 133:
 
  show ip ospf interface brief
 
  show ip ospf interface brief
 
  show ip protocols
 
  show ip protocols
 +
show ip ospf events
 +
show ip ospf border-routers
  
 +
Reset database and neighbors
 +
clear ip ospf process
  
 
[[Category:Cisco]]
 
[[Category:Cisco]]

Revision as of 15:22, 22 November 2015

Open Shortest Path First kommunicerar med multicast som alltid har ttl satt till 1. OSPF använder IP protokoll #89. RFC 2328

Type: Link State

Algorithm: Dijkstra

AD: 110

Metric: Cost (Bandwidth)

Protocols: IP

Grannskap

Neighbors måste komma överens om:

  • Subnät/Mask
  • Area
  • Timers
  • Olika router-ID
  • Flaggor: Stub, NSSA
  • MTU
  • Authentication type
  • Kompatibla nätverkstyper, DR-election eller ej

Rekommendationer

  • Set your maximum LSA settings to keep from killing weak boxes
  • Baseline your network so you know how many LSAs normally float around
  • Configure LSA warnings to alert of problems
  • Crash each type of box on your network in a lab environment so you know what it will do under stress.

Konfiguration

router ospf [process-id]

router-id for this OSPF process (in IPv4 address format)

router-id [OSPF router-id] 
log-adjacency-changes

Uppdatera reference bandwidth till 100G

router ospf 1
auto-cost reference-bandwidth 100000
exit

Enable routing on an IP network

network [network-number] [wildcard-mask] area [area-id]

Slå på routing för alla nät och styr grannskap/uppdateringar med passive-interface

passive-interface default
network 0.0.0.0 0.0.0.0 area 0
no passive-interface [interface]

Enable MD5 authentication in Area 0

area 0 authentication message-digest

Enable OSPF authentication on an interface

interface [interface]
ip ospf message-digest-key 10 md5 [password]
exit

Default route

default-information originate

DR/BDR election, multiaccess network

interface [interface]
ip ospf priority [number]  #default 1
exit

Summarization

ABR

router ospf 1
area 10 range 10.10.0.0 255.255.252.0
exit

ASBR

router ospf 1
summary-address 10.10.0.0 255.255.252.0
exit

Tuning protocol parameters

ip ospf hello-interval seconds
ip ospf dead-interval seconds
ip ospf retransmission-interval seconds
ip ospf transmit-delay seconds

Stub

No LSA type 5

area 1 stub

Stub bit is sent in hello packets

Totally Stubby

No LSA type 3,4,5. Default route only.
ABR

area 1 stub no-summary

Others

area 1 stub

NSSA

LSA type 7

area 1 nssa

NSSA Totally Stubby

LSA type 7. No LSA type 3,4.

area 1 nssa no-summary

Virtual Link

Virtual link är rekommenderat som backup- eller temporär anslutning.

R1

router ospf 1
network 10.0.1.0 0.0.0.255 area 1
network 1.1.1.0 0.0.0.255 area 0
area 1 virtual-link 3.3.3.3  #Router-ID

R3

router ospf 1
network 10.0.1.0 0.0.0.255 area 1
network 10.0.2.0 0.0.0.255 area 2
network 3.3.3.0 0.0.0.255 area 2
area 1 virtual-link 1.1.1.1  #Router-ID

Show

show ip ospf virtual-links

Diverse

Loopback

ip ospf network point-to-point
exit

MTU mismatch

ip ospf mtu-ignore

Troubleshoot

show ip ospf neighbor
ping 224.0.0.5
show ip ospf interface brief
show ip protocols
show ip ospf events
show ip ospf border-routers

Reset database and neighbors

clear ip ospf process