> For the complete documentation index, see [llms.txt](https://anida-huang.gitbook.io/computer-network/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://anida-huang.gitbook.io/computer-network/qi-zhong/cisco-eigrp.md).
# 20201104 cisco EIGRP (一)
## 課堂資料
#### Enhanced Interior Gateway Routing Protocol ( EIGRP ) 增強型內部網關路由協定：
{% embed url="" %}
#### EIGRP 設定：
{% embed url="" %}
### CSICO EIGRP
> **Enhanced Interior Gateway Routing Protocol**
* 採用 DUAL Algorithm`show ip route`
* 高級 ( Advanced ) 的 DV ( Distance Vector ) or Mixed
* IP header protocol：88
| 協定 | protocol 值 |
| :-----------------: | :--------: |
| ICMP ( 網際網路控制訊息協定 ) | 1 |
| TCP ( 傳輸控制協定 ) | 6 |
| UDP ( 用戶資料報協定 ) | 17 |
| EIGRP ( 混合型路由協定 ) | 88 |
* VLSM ( Variable Length Subnet Mask ) and CIDR ( Classless Inter Domain Routing )
* AD ( 動態距離：Administration Distance ) = 90
| 協定 | AD值 |
| :-------------------: | :-: |
| Static Route ( 靜態路由 ) | 1 |
| EIGRP ( 混合型路由協定 ) | 90 |
| OSPF ( 鏈路狀態路由協定 ) | 110 |
| RIP ( 路由資訊協定 ) | 120 |
* metrics ( 指標 )：BW ( 帶寬：BandWidth )、Delay ( 延時 )、Load ( 加載 )、Reliabily ( 可靠性 )、MTU ( 最大傳輸單元：Maximum Transmission Unit )
* trigger update：224.0.0.10 (增量更新，可靠更新：Reliabily update)
* RIPv1：255.255.255.255
* RIPv2：224.0.0.9
#### 補充
| 封包類型 | 作用 |
| ------ | -------------------- |
| Hello | 用於建立和維持 Neighborhood |
| Update | 用於傳送路由條目 |
| Ack | 用於實現可靠傳輸 |
| Query | 用於路由丟失時，向鄰居發送路由請求 |
| Reply | 收到路由請求，給予回覆 |
> EIGRP有三張表：
>
> 1. 鄰居表 ( neighbor table )
> 2. 拓樸表 ( protocol table )
> 3. 路由表 ( routing table )
## 課堂練習
### Neighbor
#### IP 設定
{% tabs %}
{% tab title="R1" %}
```
conf t
```
```
hostname R1
```
```
do writ
```
```
int e0/0
```
```
ip addr 192.168.12.1 255.255.255.0
```
```
no shut
```
{% endtab %}
{% tab title="R2" %}
```
conf t
```
```
hostname R2
```
```
do writ
```
```
int e0/0
```
```
ip addr 192.168.12.2 255.255.255.0
```
```
no shut
```
```
exit
```
```
int e0/1
```
```
ip addr 192.168.23.2 255.255.255.0
```
```
no shut
```
{% endtab %}
{% tab title="R3" %}
```
conf t
```
```
hostname R3
```
```
do writ
```
```
int e0/0
```
```
ip addr 192.168.23.3 255.255.255.0
```
```
no shut
```
{% endtab %}
{% endtabs %}
#### Route 設定
{% hint style="success" %}
使用**`router eigrp [AS No.]`**進入EIGRP設定，在同一個 AS內的EIGRP router，所有的AS Number必須相同。
{% endhint %}
{% tabs %}
{% tab title="R1" %}
```
router eigrp [AS No.]
```
```
auto-summary
```
```
network 192.168.12.0 0.0.0.255
```
{% endtab %}
{% tab title="R2" %}
```
router eigrp [AS No.]
```
```
auto-summary
```
```
network 192.168.12.0 0.0.0.255
```
```
network 192.168.23.0 0.0.0.255
```
{% endtab %}
{% tab title="R3" %}
```
router eigrp [AS No.]
```
```
auto-summary
```
```
network 192.168.23.0 0.0.0.255
```
{% endtab %}
{% endtabs %}
```
do sh ip eigrp nei
```
```
do sh ip eigrp topology
```
```
do sh ip ro eigrp
```
{% tabs %}
{% tab title="R1" %}
{% endtab %}
{% tab title="R2" %}
{% endtab %}
{% tab title="R3" %}
{% endtab %}
{% endtabs %}
{% hint style="success" %}
預設情況下，Router 之間是利用 Multicast 溝通的。
如果網路不支援 Multicast 或因某些原因 Multicast 無法順利傳送，Router 就無法成為 Neighbor。
遇到這些情況，我們使用Neighbor指令利用Unicast去傳送EIGRP封包。
{% endhint %}
{% tabs %}
{% tab title="R1" %}
```
neighbor 192.168.12.2 e0/0
```
{% endtab %}
{% tab title="R2" %}
```
neighbor 192.168.12.1 e0/1
```
```
do sh ip eigrp neighbors
```
{% hint style="danger" %}
確認有無順利建立Neighbor，可以用**`show ip eigrp nieghbors`**指令
{% endhint %}
{% endtab %}
{% endtabs %}
#### Holdtime
{% hint style="success" %}
EIGRP 有兩個 Timer，分別是 Hello Timer 及 Hold Timer。
Hello 預設值為 5秒、Hold 預設值為 15秒，也就是說 EIGRP Router 會隔 5秒傳送 Hello Message，如果收到就會維持 Neighbor 關係，反之，一旦超過15秒未收到，則會中斷 Neighbor 關係。
所以Hold Timer會從15秒開始倒數，直到收到Hello後重新計數倒數15秒。
Hello Timer 及 Hold Timer 是可以在interface下更改。
{% endhint %}
{% tabs %}
{% tab title="R2" %}
```
int e0/0
```
```
ip hello-interval eigrp ?
```
```
ip hello-interval eigrp [AS No.] ?
```
```
ip hello-interval eigrp [AS No.] 10
```
```
ip hold-time eigrp ?
```
```
ip hold-time eigrp [AS No.] ?
```
```
ip hold-time eigrp [AS No.] 30
```
```
^z
```
{% endtab %}
{% endtabs %}
{% hint style="danger" %}
切記，兩隻成為 Neighbor 也要更改。
{% endhint %}
{% tabs %}
{% tab title="R2" %}
```
clear ip eigrp [AS No.] nei
```
```
sh ip eigrp nei
```
{% endtab %}
{% endtabs %}
#### Authentication
{% hint style="success" %}
在 EIGRP Neighbor 的 interface 之間設定密碼，這樣可以避免有 Router 假扮成 Neighbor 來偷取 Router 資訊。
{% endhint %}
```
conf t
```
```
key chain MyChain
```
```
key 1
```
```
key-string MyPassword
```
```
exit
```
```
exit
```
{% tabs %}
{% tab title="R1" %}
{% endtab %}
{% tab title="R2" %}
{% endtab %}
{% endtabs %}
{% hint style="success" %}
在interface 設定 Key Chain 和 MD5 encryption
{% endhint %}
{% tabs %}
{% tab title="R1" %}
```
int e0/0
```
```
ip authentication key-chain eigrp [AS No.] MyChain
```
```
ip authentication mode eigrp [AS No.] md5
```
{% endtab %}
{% tab title="R2" %}
```
int e0/1
```
```
ip authentication key-chain eigrp [AS No.] MyChain
```
```
ip authentication mode eigrp [AS No.] md5
```
{% endtab %}
{% endtabs %}
{% hint style="success" %}
用`sh ip eigrp int detail` 可以查看Authentication 資訊
{% endhint %}
```
do sh ip eigrp int detail
```
{% tabs %}
{% tab title="R1" %}
{% endtab %}
{% tab title="R2" %}
{% endtab %}
{% endtabs %}
## 期中練習
{% tabs %}
{% tab title="01." %}
## 題目：
## 結果：
> ## R1
```
int e0/0
```
```
ip add 12.1.1.1 255.255.255.0
```
```
no shut
```
```
int e0/1
```
```
ip add 45.1.1.1 255.255.255.0
```
```
no shut
```
```
int e0/2
```
```
ip add 192.168.1.1 255.255.255.0
```
```
no shut
```
```
ip route 192.168.2.0 255.255.255.0 e0/0 12.1.1.2
```
```
ip route 192.168.2.0 255.255.255.0 e0/1 45.1.1.3 10
```
> ## R2
```
int e0/0
```
```
ip add 12.1.1.2 255.255.255.0
```
```
no shut
```
```
int e0/1
```
```
ip add 23.1.1.2 255.255.255.0
```
```
no shut
```
```
int e0/2
```
```
ip add 192.168.2.1 255.255.255.0
```
```
no shut
```
```
ip route 192.168.1.0 255.255.255.0 e0/0 12.1.1.1 10
```
```
ip route 192.168.1.0 255.255.255.0 e0/1 23.1.1.4
```
> ## R3
```
int e0/0
```
```
ip add 34.1.1.3 255.255.255.0
```
```
no shut
```
```
int e0/1
```
```
ip add 45.1.1.3 255.255.255.0
```
```
no shut
```
```
ip route 192.168.1.0 255.255.255.0 e0/1 45.1.1.1
```
> ## R4
```
int e0/0
```
```
ip add 34.1.1.4 255.255.255.0
```
```
no shut
```
```
int e0/1
```
```
ip add 23.1.1.4 255.255.255.0
```
```
no shut
```
```
ip route 192.168.1.0 255.255.255.0 e0/0 34.1.1.3
```
> ## VPC1
```
ip 192.168.1.2 255.255.0.0
```
> ## VPC2
```
ip 192.168.2.2 255.255.0.0
```
{% endtab %}
{% tab title="02." %}
## 題目：
## 結果：
> ## R1
```
hostname R1
```
```
do writ
```
```
int e0/0
```
```
ip addr 12.1.1.1 255.255.255.0
```
```
no shut
```
```
int e0/1
```
```
ip addr 192.168.1.1 255.255.255.0
```
```
no shut
```
```
exit
```
```
ip dhcp pool DHCP
```
```
network 192.168.1.0 /24
```
```
default-router 192.168.1.1
```
```
dns-server 8.8.8.8
```
> ### VPC 1
```
ip dhcp
```
```
ping 192.168.2.2
```
> ## R2
```
hostname R2
```
```
do writ
```
```
int e0/0
```
```
ip addr 12.1.1.2 255.255.255.0
```
```
no shut
```
```
int e0/1
```
```
ip addr 192.168.2.1 255.255.255.0
```
```
no shut
```
```
exit
```
```
ip dhcp pool DHCP2
```
```
network 192.168.2.0 /24
```
```
default-router 192.168.2.1
```
```
dns-server 8.8.8.8
```
> ### VPC 2
```
ip dhcp
```
```
ping 192.168.1.2
```
{% endtab %}
{% tab title="03." %}
## 題目：
## 結果：
> ## R1
```
int e0/0
```
```
ip addr 12.1.1.1 255.255.255.0
```
```
no shut
```
```
int e0/1
```
```
ip addr 45.1.1.1 255.255.255.0
```
```
no shut
```
```
int e0/2
```
```
ip addr 192.168.1.1 255.255.255.0
```
```
no shut
```
```
int lo 0
```
```
ip addr 1.1.1.1 255.255.255.255
```
```
no shut
```
```
exit
```
```
router rip
```
```
ver 2
```
```
no auto-summary
```
```
network 12.1.1.0
```
```
network 45.1.1.0
```
```
network 1.1.1.0
```
```
network 192.168.1.0
```
```
do sh run
```
> ## R2
```
int e0/0
```
```
ip addr 12.1.1.2 255.255.255.0
```
```
no shut
```
```
int e0/1
```
```
ip addr 23.1.1.2 255.255.255.0
```
```
no shut
```
```
int lo 0
```
```
ip addr 2.2.2.2 255.255.255.255
```
```
no shut
```
```
exit
```
```
router rip
```
```
ver 2
```
```
no auto-summary
```
```
network 12.1.1.0
```
```
network 23.1.1.0
```
```
network 2.2.2.0
```
```
do sh run
```
> ## R3
```
int e0/0
```
```
ip addr 34.1.1.3 255.255.255.0
```
```
no shut
```
```
int e0/1
```
```
ip addr 45.1.1.3 255.255.255.0
```
```
no shut
```
```
int lo 0
```
```
ip addr 3.3.3.3 255.255.255.255
```
```
no shut
```
```
exit
```
```
router rip
```
```
ver 2
```
```
no auto-summary
```
```
network 34.1.1.0
```
```
network 45.1.1.0
```
```
network 3.3.3.0
```
```
do sh run
```
> ## R4
```
int e0/0
```
```
ip addr 34.1.1.4 255.255.255.0
```
```
no shut
```
```
int e0/1
```
```
ip addr 23.1.1.4 255.255.255.0
```
```
no shut
```
```
int e0/2
```
```
ip addr 192.168.2.1 255.255.255.0
```
```
no shut
```
```
int lo 0
```
```
ip addr 4.4.4.4 255.255.255.255
```
```
no shut
```
```
exit
```
```
router rip
```
```
ver 2
```
```
no auto-summary
```
```
network 23.1.1.0
```
```
network 34.1.1.0
```
```
network 4.4.4.0
```
```
network 192.168.2.0
```
```
do sh run
```
> ## VPC 1
```
ip 192.168.1.2 255.255.0.0
```
```
ping 192.168.2.2
```
> ## VPC 2
```
ip 192.168.2.2 255.255.0.0
```
```
ping 192.168.1.2
```
{% endtab %}
{% endtabs %}