Category: <span>Cisco</span>

ARP (Address Resolution Protocol) is a network protocol used to map an IP address (Layer 3) to a corresponding MAC address (Layer 2) on a local area network (LAN). These are sample ways to find ARP on Cisco ASR 9000 running on IOS-XR. To find out the ARP statistics for a particular linecard, the command would be: show arp traffic location 0/X/CPU0 where X is the Slot number Example: RP/0/RSP0/CPU0:ASR9000#show arp traffic location 0/7/CPU0 ARP statistics: Recv: 2493913945 requests, 2796126129…

Cisco

Here are the step by step configuration of implementing Access-Lists or ACL on Cisco routers such as ASR9000 running on IOS-XR, utilizing the object-group for simplicity and convenience. 1.Create object-group object-group network ipv4 allowed_ip 192.168.0.0/24 object-group port allowed_port eq ssh 2. Create ACL ipv4 access-list ACL88 10 permit tcp net-group allowed_ip any port-group allowed_port 20 deny tcp any any port-group allowed_port 30 permit ipv4 any any 3. Apply ACL interface Te0/0/0/0 ipv4 access-group ACL88 egress Verification: show object-group network ipv4…

Cisco

For checking transmission links on Cisco Routers, it is good to know how to find out the optical power of 100GE modules or interfaces for troubleshooting and making sure the desired or optimal range is meet. Here are the sample commands for checking the TX/RX optical power. show controllers <100G interface name> phy Sample Output: RP/0/RSP0/CPU0:CISCO-ROUTER#show controllers HundredGigE0/1/0/0 phy PHY data for interface: HundredGigE0/1/0/0 Rx 64B66B Lane Sync PCS Virt PCS Service Block Marker Header Lane Lane Lane Lane Lock…

Cisco

PAT or Port Address Translation or also known as NAT Overloading is like a modified form of dynamic NAT where multiple inside local addresses are translated to single inside global IP address. It is the most popular form of NAT as the setup is the same what we use on our home connectivity as your Internet Service Provider (ISP) usually will only provide you 1 public IP to communicate with their internet router. Just remember the word many-to-one mapping. Objective:…

Cisco

Here are the basic configuration on implementing different types of Network Address Translation (NAT) on Cisco Routers. Fig.1 Static NAT (1-to-1 Translation) (Objective: to translate PC-1 private IP of 192.168.0.2 to public IP 200.200.200.3) Configuration: Router1 Main Static NAT configuration: ip nat inside source static <Inside local IP> <Inside global IP> Sample Config: Router1(config)# ip nat inside source static 192.168.0.2 200.200.200.3 interface FastEthernet0/0 description Connection to PC-1 ip address 192.168.0.1 255.255.255.0 ip nat inside interface FastEthernet0/1 description Connection to Router2…

Cisco

Here are the sample steps on finding the interface where the host is connected based on IP address or MAC address on Cisco Catalyst L3 Switch running on Cisco IOS Scenario 1: IP address is given, find which interface it is connected IP address: 192.168.0.35 a. Find the routing entry for the IP to know where it is connected show ip route <IP> SWITCH1#show ip route 192.168.0.35 Routing entry for 192.168.0.32/29 Known via “connected”, distance 0, metric 0 (connected, via…

Cisco

Here are the sample steps on finding the interface where the host is connected based on IP address or MAC address on Cisco Switch Nexus 7000 series running in Nexus OS. Scenario 1: IP address is given, find which interface it is connected IP address: 192.168.15.6 a. Find the routing entry for the IP to know where it is connected show ip route <IP> NEXUS7000# show ip route 192.168.15.6 IP Route Table for VRF “default” ‘*’ denotes best ucast next-hop…

Cisco

Note: This steps are based on bridge domain/VPLS  setup on Cisco ASR 9000 running Cisco IOS-XR. For normal routed interfaces,  you can find it using the command: show arp <interface> Scenario 1: IP address is given, find which interface it is connected IP address: 192.168.15.6 a. Find the routing entry for the IP to know where it is connected show route <IP> RP/0/RSP1/CPU0:ASR9K#show route 192.168.15.6 Routing entry for 192.168.15.0/29 Known via “connected”, distance 0, metric 0 (connected) Installed May 16…

Cisco

Objective: To separate management traffic from data/customer traffic on your Cisco Catalyst 4500 L3 Switch Preferably, Data and Management are into 2 separate network domains. Pre-requisite: UTP cable to connect to management port (via FastEthernet 1) and the other end is connected to a network switch to access the OOB management gateway Tested on Cisco IOS Version 15.1 (Cisco Catalyst 4948E) * * Management IP Configuration* *  1. Configure the vrf for management vrf definition management ! address-family ipv4 exit-address-family ! address-family ipv6…

Cisco

Cisco BVI (Bridge Virtual Interface) enables Layer 3 routing on a bridge group, connecting different Layer 2 networks. BVI (Bridge Group Virtual Interface) is a routed interface that represents a set of interfaces that gets bridge. Here is the sample Bridge Virtual Interface (BVI) Configuration on Cisco ASR 9000. Fig1. Configuration: RP/0/RSP1/CPU0:ASR9000#configure Configure the interface interface GigE0/0/0/0 description Connection to Server1 eth0 l2transport Configure the l2vpn l2vpn bridge group 1000 bridge-domain 1000 interface GigE0/0/0/0 routed interface BVI1000 3.Configure the Bridge…

Cisco