Switch and Router Telnet Question

hitmen

Is it possible to telnet to a switch from a router. Assuming that it is an L2 switch and there is no ip address. How can I control the switch then?

Is it possible to check the interface of a SWITCH? Again assume that it is an L2 switch. If it is a dumb switch, can I shut down one of its port?

Ivanjam

hitmen - are you studying for a particular exam?

networker050184

How would you expect to telnet to a switch with no IP on it? I think you seriously need to start from the begining and learn the fundementals.

iamme4eva

A layer 2 switch can have an IP address...

hitmen

ok. if i cant telnet the switch, then how can I enter the CLI of the switch? How can I control my switch (e.g I need to shut down a port )?

networker050184

Depends on the type of switch you have. Some have consoles, some come with default addresses and you have to hook your computer up and use a web gui. Google the vendor setup information for your specific switch model.

hitmen

if you use the term default address, do you mean that an ip address is assigned to it? Thanks.

networker050184

Again, that completely depends on the type and model of switch. Google is your friend.

NetworkVeteran

networker wrote:

I think you seriously need to start from the begining and learn the fundementals.

These questions ("If it is a dumb switch") do not seem related to the CCNA exam. hitmen, respectfully, you might benefit more from tackling the Network+ (which covers general concepts and is a bit easier) before digging into the CCNA (vendor-specific and more difficult). Both routes lead the same way, and many have found that a faster/easier route to networking mastery.

hitmen

Hi a dumb switch is basically an L2 switch.

NetworkVeteran

hitmen wrote: »

Hi a dumb switch is basically an L2 switch.

That's not quite correct. I will leave as an exercise for you to check the actual meaning.

earweed

You seriously need to hit the book. A switch has an IP address for the purpose of administration (telnet to it to use the CLI for whatever you need to do) default address is what the address for that model/manufacturer switch is and most can be changed and through your networks local DNS that switch can even be assigned a name so that you can telnet to it using a name. I believe "dumb switch" refers to an unmanaged switch that you basically do no administration on.

SephStorm

earweed is correct. Manually administer the switch through a console cable, assign an IP address to VLAN 1, assign IP addresses to the interfaces of your router, configure the devices for telnet access. You can then telnet from your PC to the switch, then from the switch to the router. Additionally you can use software like SecureCRT to have multiple telnet sessions so you could have separate sessions to the switch and router.

theodoxa

Yes, you can Telnet. You need to configure an ip address on VLAN 1 and setup a password on the vty lines and an enable password/secret if you want to be able to access privileged mode via Telnet.

SW1>enable
SW1#configure terminal
SW1(config)#enable secret cisco
SW1(config)#line vty 0 15
SW1(config-line)#transport input telnet
SW1(config-line)#password cisco
SW1(config-line)#login
SW1(config-line)#exit
SW1(config)#interface vlan 1
SW1(config-if)#ip address 192.168.0.254 255.255.255.0
SW1(config-if)#no shutdown
SW1(config-if)#end
SW1#write

Replace 192.168.0.254 with an IP Address on the appropriate subnet and 255.255.255.0 with whatever subnet mask that subnet uses. Replace "cisco" with whatever password you prefer. I use "password" since its lab equipment and I'm not worried about anyone trying to hack it.

hitmen

Can I clarify something?

In CCNA, I am taught that L2 switches can only be assigned mac addresses and not ip addresses; but L3 switches can be assigned with ip addresses.

In that case, is it possible to communicate with the L2 switch?

Is anyone here familiar with the cisco 2960 POE switch? There are only ethernet and gigabit ports but no console port.
In that case, I have to access the switch through the router??

DCD

I hate to be harsh here but for passing your CCNA and working in IT you missed a lot of fundamentals either you need to get a refund from that school or stop using **** sites.

Ivanjam

@DCD - I believe the OP is currently studying for his CCNA but, that being said, I do agree that he appears to have some rather unorthodox ideas about the way routers and switches operate.

@hitmen - would you care to enlighten us as to what material you are using to prepare for the CCNA? What books, videos, etc?

theodoxa

hitmen wrote: »

In CCNA, I am taught that L2 switches can only be assigned mac addresses and not ip addresses; but L3 switches can be assigned with ip addresses.

Switch Ports cannot be assigned an IP Address, unless its a Layer 3 switch. But, you can create a what is called a "Switch Virtual Interface" or SVI. It is a virtual interface that can be assigned an IP Address and is associated with a specific VLAN. An SVI is automatically create for the default VLAN 1. This SVI is typically used for Telnet access.

Switch virtual interface - Wikipedia, the free encyclopedia

Is anyone here familiar with the cisco 2960 POE switch? There are only ethernet and gigabit ports but no console port.
In that case, I have to access the switch through the router??

Look on the back. All of my switches (2960-24TT-L, 3550-24PWR-SMI, 3550-48-SMI, and 2950-24) all have their Console Port on the rear of the switch, though I just Googled "2960 POE" and there are some models with the Console on the front.

DCD

Ivanjam wrote: »

@DCD - I believe the OP is currently studying for his CCNA but, that being said, I do agree that he appears to have some rather unorthodox ideas about the way routers and switches operate.

@hitmen - would you care to enlighten us as to what material you are using to prepare for the CCNA? What books, videos, etc?

@Ivanjam if could take a look at these post I think you will see where I'm coming from.
http://www.techexams.net/forums/ccna-ccent/88562-question-showing-protocols.html

4/21/2013
Question On Showing of Protocols

I passed my ccna but there is still one thing I dont understand.

http://www.techexams.net/forums/ccna-ccent/89041-vlan-data-center-question.html

5/6/2013
VLAN in Data Center Question

However, in the data center that i work, the switches (data center switches not those small ethernet switches) are separated via VLAN in their topology.

hitmen

Erh .. so it is a switched virtual interface. I didnt know the term for that. All I knew was that I had to assign ip add to a vlan and the vlan had to be assigned to a port.

In the data center where I worked, we are talking about big switches or network element (NE). That is a whole new level.

Ivanjam

@DCD - I see what you mean. Maybe the OP passed his CCNA a long time ago and forgot the material somewhat.

theodoxa

Ivanjam wrote: »

@DCD - I see what you mean. Maybe the OP passed his CCNA a long time ago and forgot the material somewhat.

That's quite possible. I went through the Netacad years ago and we learned about VLANs, how to create them, etc...but I never really understood why you should create VLANs until I read Odom's book a few months back. I also forgot alot of stuff as I hadn't touched IOS since finishing Cisco IV, which is why I had to restudy everything.

hitmen

That is right. I forgot a lot of things.
I have another question.
To connect to a router console port, I use a usb to serial converter.
However, for a switch, I plug one end of the connector in the serial port. However, when I plug the other ethernet interface into my computer, it doesnt work.

What could be the problem? I can access the console port for the router not the switch.

JeanM

hitmen wrote: »

Can I clarify something?

In CCNA, I am taught that L2 switches can only be assigned mac addresses and not ip addresses; but L3 switches can be assigned with ip addresses.

In that case, is it possible to communicate with the L2 switch?

Is anyone here familiar with the cisco 2960 POE switch? There are only ethernet and gigabit ports but no console port.
In that case, I have to access the switch through the router??

So, that would mean if you buy an L2 switch and don't have a router on hand you can't access it right? No. that's not how it works. Do you have access to GNS3 or Packet Tracer or a couple cheap routers/switches?

Ivanjam

hitmen wrote: »

To connect to a router console port, I use a usb to serial converter. However, for a switch, I plug one end of the connector in the serial port. However, when I plug the other ethernet interface into my computer, it doesnt work. What could be the problem? I can access the console port for the router not the switch.

Not sure what you are saying but you connect both the switch and router via the console port to your pc in exactly the same manner.

hitmen

I googled the answer to my problem:

https://www.google.com.sg/#safe=off&sclient=psy-ab&q=cisco+2960+console+port+not+working&oq=cisco+2960+console+port&gs_l=hp.3.1.0l2j0i22i30l2.895.7992.0.9750.25.20.0.4.4.4.2048.10376.0j2j1j1j1j4j2j1j1j1.14.0....0...1c.1.21.psy-ab.PBtDKYwBzWA&pbx=1&bav=on.2,or.r_qf.&bvm=bv.49405654,d.bmk&fp=ad079f98ca72199a&biw=1366&bih=642

BTW, is there a way to add [SOLVED] to a thread like in the linux forums?