My Netwok Dictionary

IVT and multilayer switching is very commonplace in today’s network. SVI can be used to allow inter-VLAN communication on a switch multilayer, eliminating the need for a separate router to get involved.

# Ping 30.1.1.1 HOST_1

Type escape sequence to abort.

Sending 5, 100-byte ICMP Echos to 30.1.1.1, timeout is 2 seconds:.....

The success rate is 0 percent (0 / 5)

# Ping 20.1.1.1 HOST_3

Type escape sequence to abort.

Sending 5, 100-byte ICMP Echos to 20.1.1.1, timeout is 2 seconds...

The success rate is 0 percent (0 / 5) Read the rest of this entry »

These are the basic configuration commands for Catalyst 1900 Series Switch and Catalyst 2800 Series. The commends in the examples are for 1900 switch, but also serves to configure the switch 2800.

Cisco Catalyst 1900 Series Switch
Cisco Catalyst 1912 Switch
Cisco Catalyst 1924 Switch
Cisco Catalyst 2800 Series Switch
Cisco Catalyst 2802 Switch
Cisco Catalyst 2808 Switch
Cisco Catalyst 2822 Switch
Cisco Catalyst 2828 Switch

These models in particular, they are old enough, use “Firmware” as the operating system and some commands for the configuration is different to other series.

SWITCH TO APPOINT

Switch> enable
Switch # configure terminal
Switch (config) # hostname 1900 (appointed to the switch)
1900 (config) #

Set Password “ENABLE SECRET” and “ENABLE PASSWORD”

1900> enable
1900 # configure terminal
1900 (config) # enable secret password * (Enable Secret password set)
1900 (config) # enable password password ** 1-15 level (set password Enable Password)
1900 (config) #
* Enable Secret is recommended to set it generates a global key figure in the switch.
** Tier 1 is a user-mode password with different privileges. Level 15 is the enable mode password. These passwords are unencrypted. Read the rest of this entry »

Switched network creates one broadcast domain, similar to that of a VLAN powered network where all nodes belonging to the same VLAN are part of the same broadcast domain, receiving all broadcasts sent on their network.

Broadcasts can actually create problems by flooding the VLAN network.

Because the trunk links interconnecting network switches will carry these broadcasts to every switch in the network.

A switch must forward broadcast frames out all available ports in the broadcast domain because broadcasts are destined everywhere there is a listener. Read the rest of this entry »

The job of VTP is best explained from the perspective of the VTP server. All switches, by default, are VTP servers. The VTP server is where you would create, remove, or modify VLANs.
This VTP server sends an advertisement, across the domain, every 5 minutes or whenever a change is made in the VLAN database. That advertisement contains all the different VLAN names, VLAN numbers, what switches have ports in what VLANs, and a revision number. Whenever a switch receives an update with a larger revision number than the last one it applied, it applies that revision.
Keep in mind that VTP is a Cisco proprietary protocol. So, to use VTP between your switches, you must have all Cisco switches. Read the rest of this entry »

The purpose of the Spanning Tree Protocol (STP) is to prevent loops on a switched or bridged network. STP is enabled on Catalyst 1900 series switches by default. In fact, one instance of Spanning Tree is enabled for each and every VLAN.

The cost or priority of a switch interface is changed using the spantree command from interface configuration mode. Notice that the cost associated with a port can range between 1 and 65536, while the priority of a port can be set to any number between 0 and 255. Read the rest of this entry »