! Static Route Tracking, IP SLA.
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Cisco WAN - ISP1 ISP2. , , - Cisco, IP- (next-hop), :
R1(config)# ip route 0.0.0.0 0.0.0.0 2.2.2.2 R1(config)# ip route 0.0.0.0 0.0.0.0 3.3.3.3 10
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IP SLA icmp, IP- ISP1:
R1(config)# ip sla 1 R1(config)# icmp-echo 2.2.2.2 source-interface FastEthernet0/0 R1(config)# timeout 1000 R1(config)# threshold 2 R1(config)# frequency 3 R1(config)# ip sla schedule 1 life forever start-time now
, Cisco IP SLA IOS, IOS, Cisco. IOS 12.4(4) T, 15.(0)1M .
IP SLA.
- ICMP-echo - ICMP IP 2.2.2.2 3 , frequency.
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- Threshold , SLA Cisco IOS IP.
IP SLA - , SLA. IOS Track Object, :
R1(config)# track 1 ip sla 1 reachability
, IP SLA. IP- , , SLA -.
, show track, :
R1# show track Track 1 IP SLA 1 reachability Reachability is Down 1 change, last change 00:03:19 Latest operation return code: Unknown
IP SLA , ISP, :
R1(config)# ip route 0.0.0.0 0.0.0.0 2.2.2.2 track 1 R1(config)# ip route 0.0.0.0 0.0.0.0 3.3.3.3 10
track , , Up. , Down, .
! IP SLA icmp-echo