Cisco Catalyst: Configure a Trunk Port with a Native Vlan

October 26, 2018October 26, 2018 / Christopher Paquin / Leave a comment

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This post will show you how to configure a trunk port with a native vlan. In this specific example I am configuring a range of ports, but the commands for an individual interface will be the same once you have entered the config for a particular port.

First enter configuration mode

s3560#conf terminal

Now we configure the range of ports. Here we are configuring the range of ports to be a trunk, using dot1q encapsulation. We are allowing vlans 96-99, and vlan 101. We are also setting vlan101 to be the native vlan (no vlan tagging required).

s3560(config)#interface range gigabitEthernet 0/13 – 24
s3560(config-if-range)#description generic trunk ports
s3560(config-if-range)#switchport trunk encapsulation dot1q
s3560(config-if-range)#switchport mode trunk
s3560(config-if-range)#switchport trunk native vlan 101
s3560(config-if-range)switchport trunk allowed vlan 96-99,101

Now we enable spanning-tree portfast and bpduguard

s3560(config-if-range)#spanning-tree portfast

%Warning: portfast should only be enabled on ports connected to a single
host. Connecting hubs, concentrators, switches, bridges, etc… to this
interface when portfast is enabled, can cause temporary bridging loops.
Use with CAUTION

%Portfast will be configured in 13 interfaces due to the range command
but will only have effect when the interfaces are in a non-trunking mode.

s3560(config-if-range)#spanning-tree bpduguard enable
s3560(config-if-range)#end

Save your config changes

s3560#copy run start
Destination filename [startup-config]?
Building configuration…
[OK]
0 bytes copied in 1.443 secs (0 bytes/sec)
s3560#

HomeLab: Basic Syslog Configuration on Cisco Catalyst Devices

September 2, 2013November 28, 2014 / Christopher Paquin / Leave a comment

In my homelab setup I am dumping syslog on all my devices to my Linux desktop. Have not figure out what I am going to do with it yet, but I see myself either setting up Splunk or Greylog in the near future. Note, a while back I wrote a post on how to configure rsyslog on RHEL 6 – s0 if you are interested you can find that post here.

So lets get down to brass tacks and configure some freaking syslog.

In this instance we are configuring syslog redirection on a Cisco 3548xl switch. Note we are in configure terminal mode.

First we must tell our device to insert timestamps on

s-3550-1(config)#service timestamps log datetime

Now we tell the device where to send the syslog messages

s-3550-1(config)#logging 192.168.0.195

Now we tell the device which log levels to send to the syslog server. In this instance I am sending warning level messages and above. This is pretty verbose, but its a home lab so I am not worried about a slew of log messages pounding my syslog server.

s-3550-1(config)#logging trap warning

For reference I am including the logging levels below.

Emergency: 0

Alert: 1

Critical: 2

Error: 3

Warning: 4

Notice: 5

Informational: 6

Debug: 7

Now lets review what we have done with the show logging command

s-3550-1#show logging
Syslog logging: enabled (0 messages dropped, 0 flushes, 0 overruns)
    Console logging: level debugging, 13 messages logged
    Monitor logging: level debugging, 0 messages logged
    Buffer logging: level debugging, 13 messages logged
    File logging: disabled
    Trap logging: level warnings, 13 message lines logged
        Logging to 192.168.0.195, 0 message lines logged

Note that this procedure is exactly the same on my Cisco 2621 switch.

HomeLab: The Cisco 3560G

HomeLab: Simple SSH Setup on a Cisco Router

HomeLab: Cisco 3550 Switch Software Configuration Guide

Using Good Old Syslog When Troubleshooting (by Tony Fortunato)

HomeLab: Configuring the NTP Client on a Cisco Catalyst Switches

[PATCH 1/9] syslog_ns: add syslog_namespace and put/get_syslog_ns

HomeLab: Upgrading Cisco IOS Via tftp on RHEL

August 31, 2013November 28, 2014 / Christopher Paquin / Leave a comment

So I was planning on blogging about this process simply because I keep forgetting it. Being that I am in the middle of building out my lab, and have a ton of old cisco hardware with ancient images, I have found myself going through the process of updating firmware quite a bit as I tinker with different IOS images.

The first thing that you are going to need is a tftp server, which I am running on my Fedora 18 desktop. Its a very easy setup, and has been simply documented on the link below. Note the article below is specfically about how to setup a tftp server on RHEL, however the process is pretty much the same.

How to Install a tftp Server on RHEL

Now if you are looking to setup a tftp server on Windows, well I cannot help you there. If I recall you just download and install a server app, and away you go.

Below is another link that I have found that also does a fine job of explaining the Cisco side of the process simply, without getting too technical and long winded.

How to Upgrade Cisco IOS Images

HomeLab: The Cisco 3560G

HomeLab: Configuring the NTP Client on a Cisco Catalyst Switches

Configuring TFTP in Linux

Best Cisco IOS switch for home use

Cisco IOS: Basic Configuration of a Switch.

Cisco IOS : How to configure passwords.

HomeLab: The Cisco 3560G

August 18, 2013November 28, 2014 / Christopher Paquin / Leave a comment

The Cisco Catalyst 3506G is a layer 3 switch which went end-of-life in 2009. For the home lab its a pretty nice switch to have due to its layer 3 support and gigabit speed. Mine is the model seen to the left, 24 gigabit ports and 4x1gb SFP uplinks.

The Cisco Catalyst 3560 is available with one of two software images:

IP Base software includes advanced quality of service (QoS),
rate limiting, access control lists (ACLs), Open Shortest Path First
(OSPF) for routed access, and IPv6 functionality.
IP Services software provides a broader set of
enterprise-class features, including advanced hardware-based IP Unicast
and IP Multicast routing, as well as policy-based routing (PBR).

Anyway, gathered here are a few manadatory resources for the Cisco Catalyst 3560G.