{"id":32,"date":"2010-12-10T19:13:08","date_gmt":"2010-12-10T17:13:08","guid":{"rendered":"http:\/\/www.zed-network.fr\/blog\/?p=32"},"modified":"2010-12-10T19:13:08","modified_gmt":"2010-12-10T17:13:08","slug":"irdp-icmp-router-discovery-routing-protocol","status":"publish","type":"post","link":"https:\/\/zed-network.fr\/?p=32","title":{"rendered":"IRDP – ICMP Router Discovery Routing Protocol"},"content":{"rendered":"

IRDP est un protocol du type “First Hop Redundancy Protocol” comme HSRP VRRP et GLBP.<\/p>\n

Il fonctionne toutefois l\u00e9g\u00e8rement diff\u00e9rement. \u00a0IRDP envoie des paquets en multicast avec comme information une IP \u00e0 utiliser comme passerrelle par d\u00e9faut. \u00a0Il est possible pour des raisons de redondance que plusieurs \u00e9quipements envoient un paquet IRDP.<\/p>\n

Exemple :<\/p>\n

Nous avons R1 et R2 en HSRP et SW1 dans le m\u00eame sous r\u00e9seau. Pour pousser un peu plus le test nous allons configurer R1 en server DHCP.<\/p>\n

Le r\u00e9seau utilis\u00e9 est 172.16.100.0\/24<\/p>\n

R1 : 172.16.100.253 \/ R2 : 172.16.100.252.<\/p>\n

Dans l’exemple nous allons configurer un Pool DHCP permettant de n’attribuer que l’adresse 172.16.100.254. Pour cela nous avons choisis d’exclure tout simplement toutes les autres adresses.<\/p>\n

Configuration :<\/p>\n

R1(config-if)#do sh run | sec dhcp<\/pre>\n
no ip dhcp use vrf connected<\/pre>\n
ip dhcp excluded-address 172.16.100.1 172.16.100.253<\/pre>\n
ip dhcp pool DhcpPool<\/pre>\n
network 172.16.100.0 255.255.255.0<\/pre>\n
interface FastEthernet0\/0<\/pre>\n
\u00a0ip address 172.16.100.253 255.255.255.0<\/pre>\n
\u00a0ip irdp<\/pre>\n
\u00a0ip irdp multicast<\/pre>\n
\u00a0ip irdp maxadvertinterval 20<\/pre>\n
\u00a0ip irdp minadvertinterval 20<\/pre>\n
\u00a0ip irdp holdtime 60<\/pre>\n
\u00a0ip irdp preference 200<\/pre>\n
\u00a0duplex auto<\/pre>\n
\u00a0speed auto<\/pre>\n
\u00a0standby version 2<\/pre>\n
\u00a0standby 1000 ip 172.16.100.1<\/pre>\n
\u00a0standby 1000 timers msec 250 msec 750<\/pre>\n
--<\/pre>\n
\r\n
R2(config-if)#do sh run int fa0\/0<\/div>\r\n
!<\/div>\r\n
interface FastEthernet0\/0<\/div>\r\n
ip address 172.16.100.252 255.255.255.0<\/div>\r\n
ip irdp<\/div>\r\n
ip irdp multicast<\/div>\r\n
ip irdp maxadvertinterval 20<\/div>\r\n
ip irdp minadvertinterval 20<\/div>\r\n
ip irdp holdtime 60<\/div>\r\n
ip irdp preference 100<\/div>\r\n
duplex auto<\/div>\r\n
speed auto<\/div>\r\n
standby version 2<\/div>\r\n
standby 1000 ip 172.16.100.1<\/div>\r\n
standby 1000 timers msec 250 msec 750<\/div>\r\n
standby 1000 priority 110<\/div>\r\n
standby 1000 preempt<\/div><\/pre>\n
--<\/pre>\n
SW1(config-if)#do sh run | inc ip routing|gdp\r\nno ip routing\r\nip gdp irdp<\/pre>\n
SW1(config-if)#do sh run int vlan 2\r\n!\r\ninterface Vlan2\r\n ip address dhcp\r\n ip irdp\r\nend<\/pre>\n
Comme le montre les configurations et plus particuli\u00e8rement SW1 nous n’avons pas configur\u00e9 d’IP et de passerelle par d\u00e9faut.<\/div>\n
Grace au server DHCP et IRDP nous allons voir que l’on pourtant toute ces informations de configur\u00e9. Le switch est donc “reachable”.<\/div>\n
\n
SW1(config-if)#do sh ip int brief | exc una<\/pre>\n
Interface \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0IP-Address \u00a0 \u00a0 \u00a0OK? Method Status \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0Protocol<\/pre>\n
Vlan2 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0172.16.100.254 \u00a0YES DHCP \u00a0 up \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0up<\/pre>\n<\/div>\n
\n
SW1(config-if)#do sh ip route<\/pre>\n
Gateway \u00a0 \u00a0 \u00a0 \u00a0 Using \u00a0Interval \u00a0Priority \u00a0 Interface<\/pre>\n
172.16.100.252 \u00a0IRDP \u00a0 \u00a0 \u00a0 21 \u00a0 \u00a0 \u00a0 100 \u00a0 \u00a0 Vlan2<\/pre>\n
172.16.100.253 \u00a0IRDP \u00a0 \u00a0 \u00a0 21 \u00a0 \u00a0 \u00a0 200 \u00a0 \u00a0 Vlan2<\/pre>\n
Default gateway is 172.16.100.253<\/pre>\n
Host \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 Gateway \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 Last Use \u00a0 \u00a0Total Uses \u00a0Interface<\/pre>\n
ICMP redirect cache is empty<\/pre>\n<\/div>\n
Nous pouvons voir que nous recevons deux routes par d\u00e9faut cependant IRDP pr\u00e9f\u00e8re celle avec la plus grande priorit\u00e9.<\/div>\n
<\/div>\n
<\/div>\n
Debug :<\/div>\n
<\/pre>\n
\n
SW1#sh ip irdp vlan 2<\/div>\n
Vlan2 has router discovery enabled<\/div>\n
<\/div>\n
Advertisements will occur between every 450 and 600 seconds.<\/div>\n
Advertisements are sent with broadcasts.<\/div>\n
Advertisements are valid for 1800 seconds.<\/div>\n
Default preference will be 0.<\/div>\n<\/div>\n
<\/div>\n
<\/div>\n
SW1#debug ip packet<\/div>\n
\n
IP packet debugging is on<\/div>\n
SW1#<\/div>\n
*Mar \u00a01 01:36:48.947: IP: s=172.16.100.252 (Vlan2), d=224.0.0.1, len 36, rcvd 1<\/div>\n
*Mar \u00a01 01:36:54.875: IP: s=172.16.100.253 (Vlan2), d=224.0.0.1, len 36, rcvd 1<\/div>\n<\/div>\n
<\/div>\n
<\/pre>\n
\n
SW1#debug ip routing<\/div>\n
IP routing debugging is on<\/div>\n
SW1#<\/div>\n
*Mar \u00a01 01:38:28.935: GDPclient: 172.16.100.252 via IRDP, interval 20, exp 0x5AED13, priority 100<\/div>\n
*Mar \u00a01 01:38:34.883: GDPclient: 172.16.100.253 via IRDP, interval 20, exp 0x5B044A, priority 200<\/div>\n<\/div>\n
<\/div>\n","protected":false},"excerpt":{"rendered":"
IRDP est un protocol du type “First Hop Redundancy Protocol” comme HSRP VRRP et GLBP. Il fonctionne toutefois l\u00e9g\u00e8rement diff\u00e9rement. \u00a0IRDP envoie des paquets en multicast avec comme information une IP \u00e0 utiliser comme passerrelle par d\u00e9faut. \u00a0Il est possible pour des raisons de redondance que plusieurs \u00e9quipements envoient un paquet IRDP. Exemple : Nous […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_exactmetrics_skip_tracking":false,"footnotes":""},"categories":[1],"tags":[],"class_list":["post-32","post","type-post","status-publish","format-standard","hentry","category-non-classe"],"_links":{"self":[{"href":"https:\/\/zed-network.fr\/index.php?rest_route=\/wp\/v2\/posts\/32","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/zed-network.fr\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/zed-network.fr\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/zed-network.fr\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/zed-network.fr\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=32"}],"version-history":[{"count":3,"href":"https:\/\/zed-network.fr\/index.php?rest_route=\/wp\/v2\/posts\/32\/revisions"}],"predecessor-version":[{"id":35,"href":"https:\/\/zed-network.fr\/index.php?rest_route=\/wp\/v2\/posts\/32\/revisions\/35"}],"wp:attachment":[{"href":"https:\/\/zed-network.fr\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=32"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/zed-network.fr\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=32"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/zed-network.fr\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=32"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}