2950Switch - Port Status : Secure -down

Node Man

Hi Techexam friends,
I am in search of advice. I can not get two 2950 switches to speak to each other. Both will individually speak to a 2600 router, but when I connect them together, the physical port status drops to - 'NOT CONNECTED'. I presume this is some port-security setting. They are both old 2950 Switches. Both are VLAN 1 and Fa0/2. The physical port light on the front of the switches is actually dark. But lights up when I plug in a 2600 router.

Please advice.

Thank you!

MAC_Addy

Are you using a crossover cable between the switches?

I forgot to add, on your title is says port status: secure down. You might want to check your port security rules.

wgroom

As mentioned above, a crossover cable is necessary as well as both interfaces set as trunk ports. Once this is completed, I suspect the connection will go live.

networker050184

You do not need to set the interfaces to trunks for the link to come up. Switches connected on access ports are perfectly acceptable.

Node Man

I thought cross over cables were outdated and for educational purposes only, and that now, there is an autosense feature that allows straight-through cables?

networker050184

Depends on your model. If memory serves me correctly the 2950 does not support Auto MDIX.

mikeybinec

Node Man wrote: »

I thought cross over cables were outdated and for educational purposes only, and that now, there is an autosense feature that allows straight-through cables?

Construct one and plug it in your 2950 and prepare to be surprised

xnx

Crossover cable needed and obviously make sure the interfaces aren't shut down as well

networker050184

Node Man wrote: »

I thought cross over cables were outdated.....

Doesn't help that by the time equipment makes it to people's labs it's already outdated. It's cheaper that way! 2950's have been around for quite a while in technology time.

Node Man

I ordered a crimper set. I'll follow with you guys in a few days after I make a cross over cable.

Thanks!

mikeybinec

Node Man wrote: »

I ordered a crimper set. I'll follow with you guys in a few days after I make a cross over cable.

Thanks!

In fact, my avatar is of 2950s and they're wired with crossovers!

DCD

Do a show interface sowe know what were dealing with.

TechGuru80

networker050184 wrote: »

Depends on your model. If memory serves me correctly the 2950 does not support Auto MDIX.

They do not support auto mdix. Don't know off hand the lowest model that does. Is there a static Mac set? Sticky? Max amount of macs? Once those are fixed...shutdown and no shut.

MAC_Addy

Node Man wrote: »

I ordered a crimper set. I'll follow with you guys in a few days after I make a cross over cable.

Thanks!

That's more than likely the issue. Though, I'd still check the port security rules, just in case. It's also very handy to practice making cross-over cables. I've often had to make a few out in the field before, and it's always a good feeling to be able to just make them without having to look anything up. Often times, I've seen people that have "over 10 years experience" need to look up how to make an straight-thru or cross-over cable. Speaking of those people, I did seriously doubt their level of experience.

OfWolfAndMan

networker050184 wrote: »

Depends on your model. If memory serves me correctly the 2950 does not support Auto MDIX.

Here's a thread on the mdix auto command:

https://learningnetwork.cisco.com/thread/39292

I did not know 2940s supported it. Learning something everyday!

Deathmage

Crossover cable maybe outdated but I used them extensively at my job for Robot's communicating to a single computer. (yes I work with Terminator wannabe arm robots - but **** there so strong that can throw a 400 lb person 300ft!)

You would think auto-sensing would be enabled, but it's it funnier working in the good ol' days, autosensing and auto-uplink is so lame; were in the fun and mystery!

I look forward to the CCENT/CCNA study. Not that I already do it with self-taught HP Procurves at work

but everyone has to start somewhere...

xnx

Cisco is a different ball game, I had 'good' networking knowledge but it took me a while to get used to the CLI and Cisco specific things like CDP, DTP, GLBP, HSRP etc etc plus i'm doing Cisco studies along side a CSc degree.

You'll be okay once you get used to the CLI and different modes: User Exec, Privilege Exec, Global Config and subinterface mode. There's others based on context like Sub ACL mode for a named ACL.

Node Man

Thanks guys, you were right. I made a crossover cable (it took 3 tries), and it works fine. The two 2950 Switches are getting along fine.

MTciscoguy

It depends on the model of 2950, my older 2950 C2950 24 does not auto switch, my 2950 G EI does auto switch. I have made many cross over cables this last couple of weeks, so I can connect all of this stuff., seems to work pretty good right now.

TechGuru80

People are still making cables why?

mikeybinec

Node Man wrote: »

Thanks guys, you were right. I made a crossover cable (it took 3 tries), and it works fine. The two 2950 Switches are getting along fine.

YAYYYYYYYYYYYYYYYYY!!!!!!!!

MTciscoguy

TechGuru80 wrote: »

People are still making cables why?

Because I got a box of cable, 1000 feet and all of the RJ connectors and the tools that I needed without it costing me a dime, being retired, I have plenty of time to sit down and make as many cables as I want or need.

So I guess the question, would actually be,

"People are still making cables" Why not?

xnx

Errmmm.. because we can make them to the exact required length, also it takes me less than 30 seconds to make one..

MAC_Addy

TechGuru80 wrote: »

People are still making cables why?

Because we don't want to look stupid when someone says "I want my computer moved to this side of the desk.". Just kidding. It's much, much cheaper to buy a spool of 500' or 1000' of cable. You can custom fit to any need. It helps with being able to fix and problem when you're in a bind. Good knowledge to have. Speaking of which, I once went to an interview and they asked if I could make either a cross-over or straight-thru. I said yes, and they asked me to make one right there and then.

santaowns

I got 5 spools of cat 5e for free from work when they upgraded to cat6 only. I make my own cables for the experience, but I couldn't tell you the real pin out if I had to. I do know this, I had a connection between two interfaces defaulting to 10mb half instead of 1000 full because the cable was a straight through. I converted to a cross over and it negotiated fine.

theodoxa

santaowns wrote: »

...but I couldn't tell you the real pin out if I had to.

TIA/EIA-568-B: Orange-White, Orange, Green-White, Blue, Blue-White, Green, Brown-White, Brown

10/100 Crossover: University of Miami (Flip the Orange and Green Pairs)
Gigabit Crossover: Flip the Orange and Green Pairs, Flip the Blue and Brown Pairs Reversing the Striped and Non-Striped
T1 Crossover: University of Florida / Auburn University (Flip the Orange and Blue Pairs)

This way, I only have to memorize 1 color code (568-B) and then just remember how each cable varies from it.

NetwrkRaynzz

Its never a bad thing to make the cables. I'm no good at it ,but if its needed to make the job look clean then its work the effort.