• Rs232 Serial Interface Cable
• Ais Detected On Cisco Router

In a recent article, I listed five Cisco IOS Interface Configuration Mode commands I thought everyone should know. As usual, I asked readers to chime in with their suggestions in the article's discussion.

Rs232 Serial Interface Cable

Also add clock rate 1500000 to the serial interface which is clocking. AIS alarm, Framing is ESF. Cisco 2600 back to back using T1 crossover. Cisco 2911, serial port 0/0/0:0 is going to an Adtran, every now and again the port goes down. Adtran has been replaced, as well as the vwic3-4mft-t1/e1. Ran a new cable (to test) straight down the hallway, which didn't seem to fix it. When connecting a serial cable to the serial interface of the router, clocking is provided by an external device, such as a CSU/DSU device. A CSU/DSU (Channel Service Unit/Data Service Unit) is a digital-interface device used to connect a router to a digital circuit.

TechRepublic member Pwright commented on the importance of the show interfaces command and recommended that I write an article expounding on this command. Pwright made a good point: If you don't know what's really going on with the interfaces, you probably don't really know which changes you need to make. So, let's take a closer look at the show interfaces command.

The purpose of the show interfaces command is rather self-explanatory—it displays the interfaces and their status. Here's the information you can get about an interface from this command:

• Interface type
• Status
• Speed and duplex
• Encapsulation
• Errors on the interface
• The last time the interface bounced
• The last time the error counters reset
• Utilization
• IP address, subnet mask, and MAC address

In my opinion, here are the five most important uses for the show interfaces command:

• Determine if the interface is up and if the protocol is up.
• Ascertain if the interface has errors on it, especially CRC errors.
• Find out the speed and duplex of the interface (if it's Ethernet).
• Learn the current utilization and utilization over the last five minutes.
• Determine the last time an interface bounced.

Listing A offers sample output of the show interfaces command, displaying four different types of interfaces: Gigabit Ethernet, Loopback, Tunnel, and Serial. Notice how each type of interface has different types of output.

From this output, you can see that the show interfaces command generates a lot of valuable information. However, when you have 25 interfaces or more on a router, the output begins to get cumbersome. Let's look at how you can limit this output to get the information you need the most.

Know your options

The show interfaces command boasts a number of options that allow you to limit the output information. You can specify the type of interface as well as the interface number:

Using these options, you can view output for a single interface. Here's an example:

You can also view of a summary of the output from the show interfaces command. Dragon age 2 dlc decrypter md5. Using this option, you can get a summary of all interfaces and statistics about each one.

For example, say you're looking for an interface that's exceeding a 512-Kbps receive rate or perhaps you want to find any interfaces that are dropping packets from their input queue. Either way, this option can help you find that information much quicker. Here's an example:

You can also use this command with the pipe command [ ] and the begin, include, or exclude options. Here's an example of using include:

You can use begin to start the output on a line that contains a specific text string. This way, you can skip to a specific point in the output rather than looking through all of it. Here's an example:

For more information on the show interfaces command, check out Cisco's documentation. Then, share your experiences with this command—as well as your ideas for future articles—in this article's discussion.

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Ais Detected On Cisco Router

David Davis has worked in the IT industry for 12 years and holds several certifications, including CCIE, MCSE+I, CISSP, CCNA, CCDA, and CCNP. He currently manages a group of systems/network administrators for a privately owned retail company and performs networking/systems consulting on a part-time basis.