split-horizon：tunnel & eigrp classic/name

初期設定

eigrp検証.txt

2.02 KB

ファイルダウンロードについて

ダウンロード

Before

iosv-0#ping 1.1.1.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 1.1.1.1, timeout is 2 seconds:
.....
Success rate is 0 percent (0/5)
iosv-0#
iosv-0#ping 3.3.3.3
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 3.3.3.3, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 5/6/7 ms

iosv-1のlo0宛へのpingが通らない。
原因は、Hub(iosv-3)にてsplit-horizonが有効になっているから。

After

１）int tunnel配下にてスプリットホライズン無効

iosv-3(config)#int tunnel 0
iosv-3(config-if)#no ip split-horizon eigrp 100
iosv-3(config-if)#
*Jul 18 22:23:12.422: %DUAL-5-NBRCHANGE: EIGRP-IPv4 100: Neighbor 10.0.0.2 (Tunnel0) is resync: split horizon changed
*Jul 18 22:23:12.423: %DUAL-5-NBRCHANGE: EIGRP-IPv4 100: Neighbor 10.0.0.3 (Tunnel0) is resync: split horizon changed

iosv-0#ping 1.1.1.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 1.1.1.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 18/22/28 ms

トンネルインターフェースでスプリットホライズンを無効化するとpingが通る。

２）Nameモードで、int tunnel 配下で無効にする

iosv-3(config)#router eigrp 100
iosv-3(config-router)#eigrp upgrade-cli CML
Configuration will be converted from router eigrp 100 to router eigrp CML.
Are you sure you want to proceed? ? [yes/no]: yes
iosv-3(config)#
*Jul 18 22:42:26.870: EIGRP: Conversion of router eigrp 100 to router eigrp CML - Completed.

iosv-3#sh run | sec eigrp
 no ip next-hop-self eigrp 1
 no ip split-horizon eigrp 1
router eigrp CML
 !
 address-family ipv4 unicast autonomous-system 100
  !
  topology base
  exit-af-topology
  network 3.3.3.3 0.0.0.0
  network 10.0.0.0
 exit-address-family

iosv-3(config)#int tunnel 0
iosv-3(config-if)#no ip split-horizon eigrp 100

iosv-0#ping 1.1.1.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 1.1.1.1, timeout is 2 seconds:
.....
Success rate is 0 percent (0/5)

tunnel 配下でスプリットホライズンを無効にしてもpingが通らない（そもそもスプリットホライズン変更のログが流れないので、無効になっていない）

３）af-interface配下で無効にする

iosv-3(config)#router eigrp CML
iosv-3(config-router)#add ipv4 auto 100
iosv-3(config-router-af)#af-interface tunnel 0
iosv-3(config-router-af-interface)#no split-horizon
iosv-3(config-router-af-interface)#
*Jul 18 22:45:08.034: %DUAL-5-NBRCHANGE: EIGRP-IPv4 100: Neighbor 10.0.0.2 (Tunnel0) is resync: split horizon changed
*Jul 18 22:45:08.034: %DUAL-5-NBRCHANGE: EIGRP-IPv4 100: Neighbor 10.0.0.3 (Tunnel0) is resync: split horizon changed

iosv-0#ping 1.1.1.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 1.1.1.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 22/31/50 ms

EIGRPプロセス内のアドレスファミリ内のaf-interface内でスプリットホライズンを無効化する。
ちなみに、classicモードではeigrpプロセス内にスプリットホライズンをどうこうするコマンドは存在しない。

４）classicでtunnel配下に設定して、そのままnameへ移行

[Classic mode]
iosv-3#sh run | sec eigrp
no ip next-hop-self eigrp 1
no ip split-horizon eigrp 1
no ip split-horizon eigrp 100
router eigrp 100
network 3.3.3.3 0.0.0.0
network 10.0.0.0

iosv-3#sh run | sec Tunnel0
interface Tunnel0
bandwidth 1000
ip address 10.0.0.1 255.255.255.0
no ip redirects
ip mtu 1400
no ip next-hop-self eigrp 1
no ip split-horizon eigrp 1
no ip split-horizon eigrp 100
ip nhrp authentication donttell
ip nhrp network-id 99
ip nhrp holdtime 300
ip tcp adjust-mss 1360
delay 1000
tunnel source GigabitEthernet0/3
tunnel mode gre multipoint
tunnel key 100000

iosv-0#ping 1.1.1.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 1.1.1.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 13/21/28 ms

もちろんpingは通る。

iosv-3(config)#router eigrp 100
iosv-3(config-router)#eigrp upgrade-cli CML
Configuration will be converted from router eigrp 100 to router eigrp CML.
Are you sure you want to proceed? ? [yes/no]: yes
iosv-3(config)#
*Jul 18 22:50:04.246: EIGRP: Conversion of router eigrp 100 to router eigrp CML - Completed.

iosv-3#sh run | sec eigrp
router eigrp CML
 !
 address-family ipv4 unicast autonomous-system 100
  !
  af-interface Tunnel0
   no split-horizon
  exit-af-interface
  !
  topology base
  exit-af-topology
  network 3.3.3.3 0.0.0.0
  network 10.0.0.0
 exit-address-family

iosv-0#ping 1.1.1.1       
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 1.1.1.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 19/27/33 ms

トンネルインターフェースに設定したスプリットホライズンをそのままname modeのaf-interface配下に引き継いでくれる。