2514_1 2514_2
|.101 |.102
| |
| (.100) |
| |
| ------ |
+---+ SW +---+
------
| 192.168.1.0/24
pc
2514_1
priority:100 (default)
preemptあり
2514_2
priority:90
preemptなし
この状態から 2514_1をダウンさせる。
2514_2#debug standby events HSRP Events debugging is on 2514_2#2514_1がリンクダウン
2514_2# 00:13:15: SB1: Et0 Standby: c/Active timer expired (192.168.1.101) 00:13:15: SB1: Et0 Active router is local, was 192.168.1.101 00:13:15: SB: Et0 Remove active hash 192.168.1.101 (vIP 192.168.1.100) 00:13:15: SB: Et0 Add passive hash 192.168.1.101 00:13:15: SB: Et0 Add active hash 192.168.1.102 (vIP 192.168.1.100) 00:13:15: SB1: Et0 Standby router is unknown, was local 00:13:15: SB1: Et0 Standby - Active 00:13:15: %STANDBY-6-STATECHANGE: Ethernet0 Group 1 state Standby -＞ Active 00:13:15: SB1: Et0 Redundancy "hsrp-Et0-1" state Standby -＞ Active 00:13:15: SB: Et0 Redirect adv stop 00:13:15: SB1: Et0 Changing interface MAC address to 0000.0c07.ac01 2514_2# 2514_2#sho standby Ethernet0 - Group 1 Local state is Active, priority 90 Hellotime 3 sec, holdtime 10 sec Next hello sent in 1.140 Virtual IP address is 192.168.1.100 configured Active router is local Standby router is unknown Virtual mac address is 0000.0c07.ac01 8 state changes, last state change 00:00:19 IP redundancy name is "hsrp-Et0-1" (default)2514_2がactiveになった。
ここで2514_1がリンクアップすると、
2514_2# 00:14:14: SB1: Et0 Active: j/Coup rcvd from higher pri router (100/192.168.1.101) 00:14:14: SB1: Et0 Active router is 192.168.1.101, was local 00:14:14: SB: Et0 Remove active hash 192.168.1.102 (vIP 192.168.1.100) 00:14:14: SB: Et0 Remove passive hash 192.168.1.101 (frc 0) 00:14:14: SB: Et0 Add active hash 192.168.1.101 (vIP 192.168.1.100) 00:14:14: SB1: Et0 Active -＞ Speak 00:14:14: %STANDBY-6-STATECHANGE: Ethernet0 Group 1 state Active -＞ Speak 00:14:14: SB1: Et0 Redundancy "hsrp-Et0-1" state Active -＞ Speak 00:14:14: SB: Et0 Redirect adv start 00:14:24: SB1: Et0 Speak: d/Standby timer expired (unknown) 00:14:24: SB1: Et0 Standby router is local 00:14:24: SB1: Et0 Speak -＞ Standby 00:14:24: SB1: Et0 Redundancy "hsrp-Et0-1" state Speak -＞ Standbypriorityが高い2514_1が現れ、preemptが設定されているため、
2514_1がactiveになり、2514_2はstandbyになる。
2514_1#sho standby Ethernet0 - Group 1 Local state is Active, priority 100, may preempt Hellotime 3 sec, holdtime 10 sec Next hello sent in 0.044 Virtual IP address is 192.168.1.100 configured Active router is local Standby router is 192.168.1.102, priority 90 expires in 8.620 Virtual mac address is 0000.0c07.ac01 11 state changes, last state change 00:02:53 IP redundancy name is "hsrp-Et0-1" (default) 2514_2#sho standby Ethernet0 - Group 1 Local state is Standby, priority 90 Hellotime 3 sec, holdtime 10 sec Next hello sent in 2.064 Virtual IP address is 192.168.1.100 configured Active router is 192.168.1.101, priority 100 expires in 7.828 Standby router is local 10 state changes, last state change 00:00:12 IP redundancy name is "hsrp-Et0-1" (default)2台のルータのhsrpのconfigは以下のとおり。
2514_1#sho run Building configuration... ! interface Ethernet0 ip address 192.168.1.101 255.255.255.0 standby 1 ip 192.168.1.100 standby 1 preempt ! 2514_2#sho run Building configuration... interface Ethernet0 ip address 192.168.1.102 255.255.255.0 standby 1 ip 192.168.1.100 standby 1 priority 90 !2をdownさせるとstandbyがいなくなるだけで、1はactiveのまま。
2514_2をupさせると、preemptが設定されてはいるが、1のほうがpriorityが高いのでやはり1がactiveのまま。
2514_2がup
2514_1# 00:40:46: SB1: Et0 Hello in 192.168.1.102 Active pri 90 ip 192.168.1.100 00:40:46: SB1: Et0 Active: h/Hello rcvd from lower pri Active router (90/192.168.1.102) 00:40:49: SB1: Et0 Redundancy group hsrp-Et0-1 state Active -＞ Active 00:40:52: SB1: Et0 Redundancy group hsrp-Et0-1 state Active -＞ Active 00:40:56: SB1: Et0 Standby router is 192.168.1.102 2514_1# 2514_1#sho standby Ethernet0 - Group 1 Local state is Active, priority 100 Hellotime 3 sec, holdtime 10 sec Next hello sent in 2.498 Virtual IP address is 192.168.1.100 configured Active router is local Standby router is 192.168.1.102, priority 90 expires in 7.912 Virtual mac address is 0000.0c07.ac01 14 state changes, last state change 00:02:59 IP redundancy name is "hsrp-Et0-1" (default)ではここから１をdown&upさせたらどうなるか。
1がdownすると当然２がactiveになるが、1をupさせるとpriorityの高い１がactiveになった。
１にはpreemptを設定していないのに・・・・
2514_2# 00:41:49: SB1: Et0 Standby: c/Active timer expired (192.168.1.101) 00:41:49: SB1: Et0 Active router is local, was 192.168.1.101 00:41:49: SB: Et0 Remove active hash 192.168.1.101 (vIP 192.168.1.100) 00:41:49: SB: Et0 Add passive hash 192.168.1.101 00:41:49: SB: Et0 Add active hash 192.168.1.102 (vIP 192.168.1.100) 00:41:49: SB1: Et0 Standby router is unknown, was local 00:41:49: SB1: Et0 Standby -＞ Active 00:41:49: %STANDBY-6-STATECHANGE: Ethernet0 Group 1 state Standby -＞ Active 00:41:49: SB1: Et0 Redundancy "hsrp-Et0-1" state Standby -＞ Active 00:41:49: SB: Et0 Redirect adv stop 00:41:49: SB1: Et0 Changing interface MAC address to 0000.0c07.ac01 2514_2# 2514_2#sho stand Ethernet0 - Group 1 Local state is Active, priority 90, may preempt Hellotime 3 sec, holdtime 10 sec Next hello sent in 1.584 Virtual IP address is 192.168.1.100 configured Active router is local Standby router is unknown Virtual mac address is 0000.0c07.ac01 26 state changes, last state change 00:00:33 IP redundancy name is "hsrp-Et0-1" (default)2514_1がup
2514_1# 00:43:29: %LINEPROTO-5-UPDOWN: Line protocol on Interface Ethernet0, changed state to up 00:43:31: SB: Et0 Interface up 00:43:31: SB: Et0 Starting minimum interface delay (1 secs) 00:43:32: SB: Et0 Interface min delay expired 00:43:32: SB1: Et0 Init: a/HSRP enabled 00:43:32: SB1: Et0 Init -＞ Listen 00:43:32: SB1: Et0 Redundancy "hsrp-Et0-1" state Init -＞ Backup 00:43:32: SB: Et0 Redirect adv start 00:43:42: SB1: Et0 Listen: c/Active timer expired (unknown) 00:43:42: SB1: Et0 Listen -＞ Speak 00:43:42: SB1: Et0 Redundancy "hsrp-Et0-1" state Backup -＞ Speak 00:43:52: SB1: Et0 Speak: d/Standby timer expired (unknown) 00:43:52: SB1: Et0 Standby router is local 00:43:52: SB1: Et0 Speak -＞ Standby 00:43:52: SB1: Et0 Redundancy "hsrp-Et0-1" state Speak -＞ Standby 00:43:52: SB1: Et0 Standby: c/Active timer expired (unknown) 00:43:52: SB1: Et0 Active router is local 00:43:52: SB: Et0 Add active hash 192.168.1.101 (vIP 192.168.1.100) 00:43:52: SB1: Et0 Standby router is unknown, was local 00:43:52: SB1: Et0 Standby -＞ Active 00:43:52: %STANDBY-6-STATECHANGE: Ethernet0 Group 1 state Standby -＞ Active 00:43:52: SB1: Et0 Redundancy "hsrp-Et0-1" state Standby -＞ Active 00:43:52: SB: Et0 Redirect adv stop 00:43:52: SB1: Et0 Changing interface MAC address to 0000.0c07.ac01 00:43:58: SB1: Et0 Hello in 192.168.1.102 Active pri 90 ip 192.168.1.100 00:43:58: SB1: Et0 Active: h/Hello rcvd from lower pri Active router (90/192.168.1.102) 00:44:01: SB1: Et0 Redundancy group hsrp-Et0-1 state Active -＞ Active 00:44:04: SB1: Et0 Redundancy group hsrp-Et0-1 state Active -＞ Active 00:44:08: SB1: Et0 Standby router is 192.168.1.102 2514_1#2514_1#sho standby Ethernet0 - Group 1 Local state is Active, priority 100 Hellotime 3 sec, holdtime 10 sec Next hello sent in 1.010 Virtual IP address is 192.168.1.100 configured Active router is local Standby router is 192.168.1.102, priority 90 expires in 9.536 Virtual mac address is 0000.0c07.ac01 17 state changes, last state change 00:00:22 IP redundancy name is "hsrp-Et0-1" (default)では、両方preemptを消して見よう。
こうすると1を down upさせても 2がactiveのままになるはず。
2514_1がdown
2514_2#debug stand eve HSRP Events debugging is on 01:00:31: SB1: Et0 Standby: c/Active timer expired (192.168.1.101) 01:00:31: SB1: Et0 Active router is local, was 192.168.1.101 01:00:31: SB: Et0 Remove active hash 192.168.1.101 (vIP 192.168.1.100) 01:00:31: SB: Et0 Add passive hash 192.168.1.101 01:00:31: SB: Et0 Add active hash 192.168.1.102 (vIP 192.168.1.100) 01:00:31: SB1: Et0 Standby router is unknown, was local 01:00:31: SB1: Et0 Standby -＞ Active 01:00:31: %STANDBY-6-STATECHANGE: Ethernet0 Group 1 state Standby -＞ Active 01:00:31: SB1: Et0 Redundancy "hsrp-Et0-1" state Standby -＞ Active 01:00:31: SB: Et0 Redirect adv stop 01:00:31: SB1: Et0 Changing interface MAC address to 0000.0c07.ac01 2514_2# 2514_2#sho stand Ethernet0 - Group 1 Local state is Active, priority 90 Hellotime 3 sec, holdtime 10 sec Next hello sent in 0.396 Virtual IP address is 192.168.1.100 configured Active router is local Standby router is unknown Virtual mac address is 0000.0c07.ac01 34 state changes, last state change 00:00:14 IP redundancy name is "hsrp-Et0-1" (default)2514_1がup
2514_2# 01:01:26: SB1: Et0 Active: j/Coup rcvd from higher pri router (100/192.168.1.101) 01:01:26: SB1: Et0 Active router is 192.168.1.101, was local 01:01:26: SB: Et0 Remove active hash 192.168.1.102 (vIP 192.168.1.100) 01:01:26: SB: Et0 Remove passive hash 192.168.1.101 (frc 0) 01:01:26: SB: Et0 Add active hash 192.168.1.101 (vIP 192.168.1.100) 01:01:26: SB1: Et0 Active -＞ Speak 01:01:26: %STANDBY-6-STATECHANGE: Ethernet0 Group 1 state Active -＞ Speak 01:01:26: SB1: Et0 Redundancy "hsrp-Et0-1" state Active -＞ Speak 01:01:26: SB: Et0 Redirect adv start 01:01:36: SB1: Et0 Speak: d/Standby timer expired (unknown) 01:01:36: SB1: Et0 Standby router is local 01:01:36: SB1: Et0 Speak -＞ Standby 01:01:36: SB1: Et0 Redundancy "hsrp-Et0-1" state Speak -＞ Standby 2514_2# 2514_2#sho stand Ethernet0 - Group 1 Local state is Standby, priority 90 Hellotime 3 sec, holdtime 10 sec Next hello sent in 1.296 Virtual IP address is 192.168.1.100 configured Active router is 192.168.1.101, priority 100 expires in 7.560 Standby router is local 36 state changes, last state change 00:01:08 IP redundancy name is "hsrp-Et0-1" (default)あれ、おかしいな、１がactiveになった・・・
これは、２台のルータを接続しているcatalystのポートがデフォルト設定のままのため、link upまでに３０秒かかっていることが原因と思われる。portfastを設定して即時リンクアップするようにしたら１が復帰しても2がactiveのままになった。
では、portfastを設定した状態で、priorityの低い２だけにpreemptを設定した場合をもう一度やってみる。
まず、1:active, 2:standyで、1をdown upさせた場合。
2514_2#sho stand Ethernet0 - Group 1 Local state is Standby, priority 90, may preempt Hellotime 3 sec, holdtime 10 sec Next hello sent in 0.750 Virtual IP address is 192.168.1.100 configured Active router is 192.168.1.101, priority 100 expires in 9.340 Standby router is local 10 state changes, last state change 00:00:13 IP redundancy name is "hsrp-Et0-1" (default)2514_1がDOWN
2514_2# 00:16:35: SB1: Et0 Standby: c/Active timer expired (192.168.1.101) 00:16:35: SB1: Et0 Active router is local, was 192.168.1.101 00:16:35: SB: Et0 Remove active hash 192.168.1.101 (vIP 192.168.1.100) 00:16:35: SB: Et0 Add passive hash 192.168.1.101 00:16:35: SB: Et0 Add active hash 192.168.1.102 (vIP 192.168.1.100) 00:16:35: SB1: Et0 Standby router is unknown, was local 00:16:35: SB1: Et0 Standby -＞ Active 00:16:35: %STANDBY-6-STATECHANGE: Ethernet0 Group 1 state Standby -＞ Active 00:16:35: SB1: Et0 Redundancy "hsrp-Et0-1" state Standby -＞ Active 00:16:35: SB: Et0 Redirect adv stop 00:16:35: SB1: Et0 Changing interface MAC address to 0000.0c07.ac01 2514_2# 2514_2#sho stand Ethernet0 - Group 1 Local state is Active, priority 90, may preempt Hellotime 3 sec, holdtime 10 sec Next hello sent in 2.712 Virtual IP address is 192.168.1.100 configured Active router is local Standby router is unknown Virtual mac address is 0000.0c07.ac01 11 state changes, last state change 00:00:09 IP redundancy name is "hsrp-Et0-1" (default)2514_1がup
2514_2#sho stand Ethernet0 - Group 1 Local state is Active, priority 90, may preempt Hellotime 3 sec, holdtime 10 sec Next hello sent in 2.684 Virtual IP address is 192.168.1.100 configured Active router is local Standby router is 192.168.1.101, priority 100 expires in 9.036 Virtual mac address is 0000.0c07.ac01 11 state changes, last state change 00:00:55 IP redundancy name is "hsrp-Et0-1" (default)1のほうがpriorityが高いが、preemptを設定していないので、2がactiveのままとなる。
では、preemptを設定した2をdown upさせる。
2514_2がdown
2514_2# 00:17:53: %LINEPROTO-5-UPDOWN: Line protocol on Interface Ethernet0, changed state to down 00:17:53: SB: Et0 Interface down 00:17:53: SB1: Et0 Active: b/HSRP disabled 00:17:53: SB1: Et0 Active router is unknown, was local 00:17:53: SB: Et0 Remove active hash 192.168.1.102 (vIP 192.168.1.100) 00:17:54: SB1: Et0 Standby router is unknown, was 192.168.1.101 00:17:54: SB1: Et0 Active -＞ Init 00:17:54: %STANDBY-6-STATECHANGE: Ethernet0 Group 1 state Active -＞ Init 00:17:54: SB1: Et0 Redundancy "hsrp-Et0-1" state Active -＞ Init 2514_2# 2514_2#sho standby Ethernet0 - Group 1 Local state is Init (interface down), priority 90, may preempt Hellotime 3 sec, holdtime 10 sec Virtual IP address is 192.168.1.100 configured Active router is unknown Standby router is unknown 12 state changes, last state change 00:00:06 IP redundancy name is "hsrp-Et0-1" (default) 2514_2# 2514_1#debug stand eve HSRP Events debugging is on 2514_1#2514_1#sho stand Ethernet0 - Group 1 Local state is Active, priority 100 Hellotime 3 sec, holdtime 10 sec Next hello sent in 0.096 Virtual IP address is 192.168.1.100 configured Active router is local Standby router is unknown Virtual mac address is 0000.0c07.ac01 14 state changes, last state change 00:00:43 IP redundancy name is "hsrp-Et0-1" (default)2514_2がup
2514_1#2514_1#sho stand Ethernet0 - Group 1 Local state is Active, priority 100 Hellotime 3 sec, holdtime 10 sec Next hello sent in 0.038 Virtual IP address is 192.168.1.100 configured Active router is local Standby router is 192.168.1.102, priority 90 expires in 8.944 Virtual mac address is 0000.0c07.ac01 14 state changes, last state change 00:01:27 IP redundancy name is "hsrp-Et0-1" (default) 00:19:18: SB1: Et0 Standby router is 192.168.1.102２にはpreemptを設定してあるが、priorityが１より低いため、その機能は有効にならない。
HSRPはRFC2281、VRRPはRFC2338で定義（？）されている。
しかし2281はCategory: informationalで、2338は Proposal Standardである。
HSRPはcisco独自の規格であり、VRRPは汎用化されたためにそうなっているようであるが、
VRRPはHSRPを元に作られたようで、動きもそっくりなようだ。
・・・
やっぱり実際に設定して動かして見ないとわかんないね。
portfastとのカラミでおかしなことになるのもいい勉強になった。