telnet and aux questions

Discussion in 'General Cisco Certifications' started by kobem, Mar 11, 2007.

  1. kobem

    kobem Megabyte Poster

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    telnet questions

    1- for example i implement a lab application and have two
    routers and two switches (not important the rest)

    i saved the configuration on one of the routers but
    we couldn't finish the lab that day

    other day console cable didn't work , i tried to
    "telnet" on computer to routers ethernet interface

    "i have given ip address to the ethernet interface"
    one day ago
    but i couldn't telnet the router from pc

    (since i configured router one day ago , i can telnet ?)



    and other telnet question : do i need to plug the ethernet cable
    while telnetting?(due to the event above)

    .....................................................

    my aux question: for example i am in miami and have to
    reach the router in los angeles (think router in los angeles
    is down and have to activate)


    should i telnet or use aux and what is the difference
    between them in terms of where i use telnet and where
    aux?
     
    Certifications: CCNA
  2. Headache

    Headache Gigabyte Poster

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    Regarding the telnet question, did you enter the password and login ? Because if you didn't, then the router wouldn't let you in.

    i.e

    Line vty 0 4
    login
    password kobem
     
    Certifications: CCNA
    WIP: CCNP
  3. Headache

    Headache Gigabyte Poster

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    Another thing to check is whether your PC's ethernet port and the router's ethernet port are in the same subnet. If they aren't, then you might consider changing either the ip address and subnet mask on your PC or the ip address and subnet mask on your router.

    EDIT: Sorry, I forgot you said your console connection isn't working
     
    Certifications: CCNA
    WIP: CCNP
  4. NetEyeBall

    NetEyeBall Kilobyte Poster

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    Buy another console cable, and research the configuration for how to set up telnet on a Cisco Router.

    Like Headache said there is only a couple of commands to set up, but you have to do it BEFORE you try to telnet to the router/switch. Otherwise you better have the console cable ready.
     
    Certifications: CCNA, A+, N+, MCSE 4.0, CCA
    WIP: CCDA, CCNP, Cisco Firewall
  5. kobem

    kobem Megabyte Poster

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    you passed some of my ques. without looking at:D

    line vty 0 4 .. but we enter these in hyperterm
    i meant command console on pc


    - first typed "o" (for open)
    then telnet "router's eth interface ip" but it said failed
    why?

    .....................
     
    Certifications: CCNA
  6. NetEyeBall

    NetEyeBall Kilobyte Poster

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    If you set it up properly all you have to do is open a command prompt and telnet to the IP Address of the router. It will ask for a username and password.

    You have to set up the VTY with a password and the login command.

    The only other possibility is that you are using SSH, but if you are using SSH it wouldn't be on a router that you just set up.
     
    Certifications: CCNA, A+, N+, MCSE 4.0, CCA
    WIP: CCDA, CCNP, Cisco Firewall
  7. NetEyeBall

    NetEyeBall Kilobyte Poster

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    Post the config of your router and we can tell more why it isn't working.

    But you will have to either telnet or use a console cable to get to the router to copy the show run.
     
    Certifications: CCNA, A+, N+, MCSE 4.0, CCA
    WIP: CCDA, CCNP, Cisco Firewall
  8. Headache

    Headache Gigabyte Poster

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    *giggle*

    Sorry.

    Catch 22.
     
    Certifications: CCNA
    WIP: CCNP
  9. Headache

    Headache Gigabyte Poster

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    Kobem, let me ask you a few questions:

    1. Is your console connection definitely broken ?

    2. What ip address and subnet mask did you put on the router's ethernet interface ?

    3. What ip address and subnet mask do you have your PC's ethernet port ?

    4. You have two routers. The one you can't get into and a second one. Are they both connected by serial cable ? Is there connectivity between the two routers ? Is the console port on the other router working ?

    Answer these questions and we might be able to devise a solution based on what answers you provide.

    Cheers.
     
    Certifications: CCNA
    WIP: CCNP
  10. NetEyeBall

    NetEyeBall Kilobyte Poster

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    Certifications: CCNA, A+, N+, MCSE 4.0, CCA
    WIP: CCDA, CCNP, Cisco Firewall
  11. r.h.lee

    r.h.lee Gigabyte Poster

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    Headache,

    If a password was not configured for the router, then the router will let you in. If a password was configured for the router, then the router will let you in IF you type in the telnet password.
     
    Certifications: MCSE, MCP+I, MCP, CCNA, A+
    WIP: CCDA
  12. Headache

    Headache Gigabyte Poster

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    Sorry, I've never been able to telnet without first setting up password login. Anytime I try that, it would come up with the message "password not configured" and kick me right out again.

    But that's just me.

    In any case, all I am doing, in my own limited way, is trying to come up with a way to help kobem to resolve his problem. But now that you've arrived, I am happy to abdicate my role to your superior wisdom.

    Cheers.
     
    Certifications: CCNA
    WIP: CCNP
  13. NetEyeBall

    NetEyeBall Kilobyte Poster

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    Two Cisco Devices directly connected via back to back serial:

    No VTY password setup results in the following when you telnet:

    Router#192.168.1.1
    Trying 192.168.1.1 ... Open
    Password required, but none set
    [Connection to 192.168.1.1 closed by foreign host]

    If you try to configure the VTY to be able to login without a password it generates the following error (When you are configing the VTY Lines):

    Router(config)#line vty 0 4
    Router(config-line)#login
    % Login disabled on line 66, until 'password' is set
    % Login disabled on line 67, until 'password' is set
    % Login disabled on line 68, until 'password' is set
    % Login disabled on line 69, until 'password' is set
    % Login disabled on line 70, until 'password' is set

    VTY Lines setup with password and login result in the following (When you telnet to the device):

    Router#192.168.1.2
    Trying 192.168.1.2 ... Open
    User Access Verification
    Password:

    However you will only get into User Mode unless the Enable Password is set allowing you into Privledged Mode.

    Router>en
    % No password set

    You could also set the VTY with the Login Local command (Config):

    Line VTY 0 4
    Login Local

    but you will also need to configure a user. If you don't configure a user account then you will get the following out put (When you telnet):

    Router#192.168.1.2
    Trying 192.168.1.2 ... Open
    User Access Verification
    Username:
    Username:
    Username:
    Username:

    So you need to configure a user account (Config):

    Router(config)#username CISCOADMIN privilege 15 secret 0 Cisco

    and when you do so you get the following (Telnet):

    Router#192.168.1.2
    Trying 192.168.1.2 ... Open
    User Access Verification
    Username: CISCOADMIN
    Password:
    Router#

    So the best advice is for Kobem to do some research on how he wants to set up the user accounts that will access his routers. Either user accounts or secret password? Also he needs to wire up a console cable or several in case of emergency. Also needs to learn how to configure the VTY Lines on his equipment.

    Unless I am missing something in his question....which is always a possibility...trust me! :D
     
    Certifications: CCNA, A+, N+, MCSE 4.0, CCA
    WIP: CCDA, CCNP, Cisco Firewall
  14. Spice_Weasel

    Spice_Weasel Kilobyte Poster

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    There may be a bit of confusion over vty login. On vty lines setting "no login" allows access without any password required. Issuing the login command sets the vty line to require some form of authentication/password. If you issue the login command but don't specify a password or authentication method you will not be able to connect to that vty line.

    But remember, "no login" allows access without any password or authentication - I've met some people who thought it disabled logins on the vty line, and tried using "no login" to secure the line!

    Spice_Weasel
     
    Certifications: CCNA, CCNP, CCIP, JNCIA-ER, JNCIS-ER,MCP
    WIP: CCIE
  15. kobem

    kobem Megabyte Poster

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    you still didn't look at my aux question

    also

    about telnet (tried telnet from pcs command console)
    but after telnet command entered

    it turned me connection to router from port 23 failed
    so it didn't ask username and password ok?
     
    Certifications: CCNA

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