- Cisco mac address table default trunk filtering how to#
- Cisco mac address table default trunk filtering full#
- Cisco mac address table default trunk filtering mac#
Cisco mac address table default trunk filtering mac#
Total Addresses in System (excluding one mac per port) : 0 Secure Port MaxSecureAddr CurrentAddr SecurityViolation Security Action Switchport port-security mac-address 0015.99d2.99fd Switch(config-if)#switchport port-security violation protect Switch(config-if)#switchport port-security maximum 1
Switch(config-if)#switchport port-security Switch(config)#interface FastEthernet 0/1 We are going to keep it simple and work with FastEthernet port 0/1.Įnter configuration commands, one per line. The port shuts down when the maximum number of secure MAC addresses is exceeded. Maximum number of secure MAC addresses per port The tutorial also shows you have to connect to the Cisco device via the console cable and a serial-to-USB adapter.
Cisco mac address table default trunk filtering how to#
To ensure you also have the default values to follow along with this tutorial I suggest following my previous post on how to reset your switch to the factory defaults. The table below lists the default values on each port for the Cisco 2960.
Cisco mac address table default trunk filtering full#
If you limit the number of secure MAC addresses to one and assign a single secure MAC address, the device attached to that port has the full bandwidth of the port. When you assign secure MAC addresses to a secure port, the port does not forward ingress traffic that has source addresses outside the group of defined addresses. You can use port security with dynamically learned and static MAC addresses to restrict a port’s ingress traffic by limiting the MAC addresses that are allowed to send traffic into the port. From Understanding Port Security – Chapter 62 – Configuring Port Security Since both hosts now know each other MAC addresses, the communication can occur.We are going to configure basic, no frills, port security on the Cisco Catalyst 2960.R1 receives the reply and updates the ARP table with the MAC address of Host A.The host also updates its own ARP table with the MAC address of the Gigabit0/0 interface on R1. Host A receives the frame and sends its MAC address to R1 (ARP reply).If it is not, R1 will send an ARP request to the broadcast MAC address of FF:FF:FF:FF:FF:FF. R1 checks its ARP table to find out whether the Host A’s MAC address is known.The subnet on which Host A resides is a directly connected subnet. Here are the steps R1 needs to take before forwarding frames to Host A: Interface – the interface on R1 on which the corresponding host is connected.For Ethernet, this value will always be ARPA. Hardware – the MAC address of the host with the corresponding IP address.Each time an entry is used, the age will be reset back to zero. 6 in this column means that the entry was last used 6 minutes ago. Age – by default, an entry will be removed from the ARP table if it wasn’t used in 240 minutes.Address – the IP address associated with the MAC address, in our case the IP address of Host A.Protocol – the protocol type, almost always Internet.
Here is a brief description of each field: Consider the entry for Host A: Protocol Address Age (min) Hardware Addr Type Interface The ARP table also lists the MAC addresses of the two connected hosts. The – in the age column indicates that the entry will never be timed out.
The ARP table contains two entries for R1’s own two interfaces with the IP address of 10.0.0.1 and 172.16.0.1. Internet 10.0.0.10 6 73 ARPA GigabitEthernet0/0 Protocol Address Age (min) Hardware Addr Type Interface Here is the output of the R1’s ARP table: R1#show ip arp Before exchanging frames with either host, R1 will need to know their MAC addresses. The IP-to-MAC address mapping are kept in the router’s ARP table. Just like regular hosts, if a Cisco router wants to exchange frames with a host in the same subnet, it needs to know its MAC address.