Here an example of 1 corporate router with connections to 3 branche routers. Each connection is with a serial interface. The routing is done with OSPF.The example is created with Cisco Packet Tracer. Partial running-config of CORP CORP# ! OUTPUT OMITTED ! interface Loopback0 ip address 1.1.1.1 255.255.255.255 ! interface Tunnel0 ip address 10.0.10.1 255.255.255.252 […]
Category: Archive 2019
Cisco CLI
aaa authentication line default methode1 methode2 aaa authentication login default aaa new model clear ip ospf proces default-information originate “interface sub-command: bandwidth speed” “interface sub-command: ip mtu xxx ip ospf cost x ipv6 mtu xxx” ip address negotiated ip host Server 172.16.20.254 ipv6 access-list Block_Telnet ipv6 host Server1 2001:db8:3c4d:1:a14c:8c3:2d1:be3d “OSPF sub-command: auto-cost reference-bandwidth speed router-id […]
Cisco command: show (3)
show access-lists show cdp show cdp interface show cdp neighbors show cdp neighbors detail show cdp traffic show host show interace fa0/0 show interfaces show interfaces fastEthernet 0/15 switchport show interfaces trunk show ip bgp show ip bgp neighbors show ip bgp summary show ip default-gateway show ip eigrp events show ip eigrp interfaces show […]
Port-channel
An example of port-channel with 3 switches. Partial config of switch SW1: interface Port-channel1 switchport trunk encapsulation dot1q switchport mode trunk ! interface Port-channel2 switchport trunk encapsulation dot1q switchport mode trunk ! interface GigabitEthernet0/0 switchport trunk encapsulation dot1q switchport mode trunk media-type rj45 negotiation auto channel-group 1 mode active ! interface GigabitEthernet0/1 switchport trunk encapsulation […]
Cisco command: show (2)
Some show commands which might come in handy. EIGRP show ip protocols show ip eigrp neighbors show ip eigrp topology show ip route eigrp show ip eigrp topology all-links show ip eigrp interface show ipv6 protocols show ipv6 eigrp neighbors show ipv6 route eigrp show ipv6 eigrp interface CDP show cdp show cdp neighbors show […]
Tunnel mode gre ip
Configuring a tunnel between 2 Cisco 2811 routers, done in Cisco Packet Tracer. Partial config of RouterA RouterA#show running-config ! ! interface Tunnel0 ip address 192.168.10.1 255.255.255.0 mtu 1476 tunnel source Serial1/0 tunnel destination 63.1.1.2 ! ! interface FastEthernet0/0 ip address 10.0.10.1 255.255.255.0 duplex auto speed auto ! interface Serial1/0 ip address 63.1.1.1 255.255.255.252 clock […]
RIP vs OSPF vs EIGRP
The basic configuration of these protocols compared to each other. RIP OSPF EIGRP configure terminal configure terminal configure terminal router rip router ospf 1 router eigrp 10 version 2 network 10.0.10.0 network 10.0.10.0 0.0.255.255 area 0 network 10.0.10.0
OSPF – multiple Area
A routing example of 3 area’s created with GNS3. Show running-configs of the OSPF section of all 7 routers R1#show running-config | section ospf router ospf 1 network 10.0.0.0 0.0.255.255 area 0 R2#show running-config | section ospf router ospf 1 network 10.0.0.0 0.0.255.255 area 0 network 192.0.0.0 0.255.255.255 area 1 R3#show running-config | section ospf […]
IPv4 vs IPv6
Here a IPv4 vs IPv6 comparison table.You can find the full table here: https://www.ripe.net/manage-ips-and-asns/ipv6/ipv6-address-types IPv6 IPv6 Example Designation and explanation IPv4 Equivalent ::/128 Unspecified 0.0.0.0 ::1/128 Loopback 127.0.0.1 ::ffff:0:0/96 ::ffff:192.0.2.47 IPv4-Mapped No equivalent fc00::/7 fdf8:f53b:82e4::53 Unique Local Addresses (ULAs) 10.0.0.0/8 172.16.0.0/12 192.168.0.0/16 fe80::/10 fe80::200:5aee:feaa:20a2 Link-Local Addresses 169.254.0.0/16 2001:0000::/32 2001:0000:4136:e378: 8000:63bf:3fff:fdd2 Teredo No equivalent 2002::/16 2002:cb0a:3cdd:1::1 […]
IPv6 example 1
========== SHOW INTERFACES ========== RouterA#show interfaces GigabitEthernet0/0 is up, line protocol is up Hardware is iGbE, address is 0ca8.ba4f.9b00 (bia 0ca8.ba4f.9b00) Description: Uplink RouterB RouterB#show interfaces GigabitEthernet0/0 is up, line protocol is up Hardware is iGbE, address is 0ca8.baee.5700 (bia 0ca8.baee.5700) Description: Uplink RouterA ========== CONFIGURE INTERFACES ========== RouterA#configure terminal RouterA(config)#interface gigabitEthernet 0/0 RouterA(config-if)#ipv6 address […]