2600 NM-16A SSH Terminal Server: Termination & Break Sends

Discussion in 'Cisco' started by Randal T. Rioux, Sep 16, 2006.

  1. -----BEGIN PGP SIGNED MESSAGE-----
    Hash: RIPEMD160

    Greetings folks. As you can tell from the subject line, I have a 2620
    (IOS 12.3) with an NM-16A async module setup as a terminal server. This
    is my first time configuring a Cisco system as such, and I have a couple
    questions.

    First, after connecting to the console of another system (Sun Netra X1)
    from this router via the following command:

    ssh -p 2033 192.168.0.5

    I'd like to send a break signal to drop to OpenBoot PROM. How would I do
    that?

    Second, once I'm finished - how do I exit the session? The only way I
    have been doing it is killing the SSH client session, which isn't very
    nice or clean. What is the proper way to terminate this SSH terminal
    server connection from the router?

    Thanks all!

    - --
    Randal T. Rioux | Procyon Labs
    IT Security R&D and Consulting
    Virtual: www.procyonlabs.com
    Physical: DC / Baltimore
    PGP: gpg --keyserver pgp.mit.edu --recv-keys 0xD08D1941


    -----BEGIN PGP SIGNATURE-----
    Version: GnuPG v1.4.5 (GNU/Linux)
    Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org

    iD8DBQFFC4Z5RrGMQdCNGUERA/o7AJsHnFI7X+O1fvCNoQEmrhwzbgG4mQCeKx4T
    bOP1Sq7i68gnL37hP69ODbg=
    =J0jB
    -----END PGP SIGNATURE-----

    --
    Posted via a free Usenet account from http://www.teranews.com
     
    Randal T. Rioux, Sep 16, 2006
    #1
    1. Advertising

  2. Randal T. Rioux

    Merv Guest

    For reverse telnet it is by pressing the shift key, the ctrl key and
    the 6 key usual show as shift-ctrl6

    do not know if this will work for reverse ssh
     
    Merv, Sep 16, 2006
    #2
    1. Advertising

  3. ~ Greetings folks. As you can tell from the subject line, I have a 2620
    ~ (IOS 12.3) with an NM-16A async module setup as a terminal server. This
    ~ is my first time configuring a Cisco system as such, and I have a couple
    ~ questions.
    ~
    ~ First, after connecting to the console of another system (Sun Netra X1)
    ~ from this router via the following command:
    ~
    ~ ssh -p 2033 192.168.0.5
    ~
    ~ I'd like to send a break signal to drop to OpenBoot PROM. How would I do
    ~ that?

    router(config)#ip ssh break-string STRING

    This was added in 12.3(2). 12.3(16) / 12.4(3) fixed a problem where
    a single character break-string wasn't recognized till you enter <CR>.

    http://www.cisco.com/en/US/products...erence_chapter09186a0080444bc0.html#wp1144695

    ~
    ~ Second, once I'm finished - how do I exit the session? The only way I
    ~ have been doing it is killing the SSH client session, which isn't very
    ~ nice or clean. What is the proper way to terminate this SSH terminal
    ~ server connection from the router?
    ~
    ~ Thanks all!

    Clearing the SSH session from the client side is the best practice for
    disconnecting, and (as far as I'm concerned) is "nice and clean" enough.

    So use the IOS exec terminal escape character (by default, ctrl-^ aka
    "control-shift-6") followed by X.

    Regards,

    Aaron

    ---


    ~
    ~ - --
    ~ Randal T. Rioux | Procyon Labs
    ~ IT Security R&D and Consulting
    ~ Virtual: www.procyonlabs.com
    ~ Physical: DC / Baltimore
    ~ PGP: gpg --keyserver pgp.mit.edu --recv-keys 0xD08D1941
    ~
    ~
    ~ -----BEGIN PGP SIGNATURE-----
    ~ Version: GnuPG v1.4.5 (GNU/Linux)
    ~ Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org
    ~
    ~ iD8DBQFFC4Z5RrGMQdCNGUERA/o7AJsHnFI7X+O1fvCNoQEmrhwzbgG4mQCeKx4T
    ~ bOP1Sq7i68gnL37hP69ODbg=
    ~ =J0jB
    ~ -----END PGP SIGNATURE-----
     
    Aaron Leonard, Sep 18, 2006
    #3
  4. On Sat, 16 Sep 2006 01:07:06 -0400, Randal T. Rioux wrote:

    > -----BEGIN PGP SIGNED MESSAGE-----
    > Hash: RIPEMD160
    >
    > Greetings folks. As you can tell from the subject line, I have a 2620
    > (IOS 12.3) with an NM-16A async module setup as a terminal server. This
    > is my first time configuring a Cisco system as such, and I have a couple
    > questions.
    >
    > First, after connecting to the console of another system (Sun Netra X1)
    > from this router via the following command:
    >
    > ssh -p 2033 192.168.0.5
    >
    > I'd like to send a break signal to drop to OpenBoot PROM. How would I do
    > that?
    >
    > Second, once I'm finished - how do I exit the session? The only way I
    > have been doing it is killing the SSH client session, which isn't very
    > nice or clean. What is the proper way to terminate this SSH terminal
    > server connection from the router?
    >


    Ok - it looks like all this is handled by the SSH client. For example,
    I'm using OpenSSH on Gentoo Linux. To exit the session, I need to use
    the default sequence "~." (tilde-period). Because the IOS version I'm
    using doesn't support SSH v2, the send-break sequence (for this SSH
    client) of "~B" doesn't work (apparently that is a v2 only feature).

    So, unless there is a way for an SSH v1 (err, 1.5) client to send a
    break signal, I'm stuck with Telnet only connections. Grrr.

    I did a quick how-to for this on my site:

    http://www.procyonlabs.com/guides/Cisco/IOS/terminal_server

    Thanks,
    Randy
     
    Randal T. Rioux, Sep 19, 2006
    #4
  5. On Mon, 18 Sep 2006 10:36:17 -0700, Aaron Leonard wrote:

    > ~ Greetings folks. As you can tell from the subject line, I have a 2620
    > ~ (IOS 12.3) with an NM-16A async module setup as a terminal server. This
    > ~ is my first time configuring a Cisco system as such, and I have a couple
    > ~ questions.
    > ~
    > ~ First, after connecting to the console of another system (Sun Netra X1)
    > ~ from this router via the following command:
    > ~
    > ~ ssh -p 2033 192.168.0.5
    > ~
    > ~ I'd like to send a break signal to drop to OpenBoot PROM. How would I do
    > ~ that?
    >
    > router(config)#ip ssh break-string STRING
    >
    > This was added in 12.3(2). 12.3(16) / 12.4(3) fixed a problem where
    > a single character break-string wasn't recognized till you enter <CR>.
    >
    > http://www.cisco.com/en/US/products...erence_chapter09186a0080444bc0.html#wp1144695
    >
    > ~
    > ~ Second, once I'm finished - how do I exit the session? The only way I
    > ~ have been doing it is killing the SSH client session, which isn't very
    > ~ nice or clean. What is the proper way to terminate this SSH terminal
    > ~ server connection from the router?
    > ~
    > ~ Thanks all!
    >
    > Clearing the SSH session from the client side is the best practice for
    > disconnecting, and (as far as I'm concerned) is "nice and clean" enough.
    >
    > So use the IOS exec terminal escape character (by default, ctrl-^ aka
    > "control-shift-6") followed by X.
    >


    Looks like I'm a few versions behind that capability then!

    Thanks for the follow up, Aaron.

    Randy



    Posted Via Usenet.com Premium Usenet Newsgroup Services
    ----------------------------------------------------------
    ** SPEED ** RETENTION ** COMPLETION ** ANONYMITY **
    ----------------------------------------------------------
    http://www.usenet.com
     
    Randal T. Rioux, Sep 19, 2006
    #5
    1. Advertising

Want to reply to this thread or ask your own question?

It takes just 2 minutes to sign up (and it's free!). Just click the sign up button to choose a username and then you can ask your own questions on the forum.
Similar Threads
  1. CCIE Wannabe

    Terminal Server Problem (break sequence)

    CCIE Wannabe, Oct 4, 2004, in forum: Cisco
    Replies:
    1
    Views:
    1,781
    Hansang Bae
    Oct 5, 2004
  2. =?Utf-8?B?c2hhb2xpbmRy?=
    Replies:
    1
    Views:
    1,079
  3. Replies:
    22
    Views:
    4,652
    Aaron Leonard
    Mar 17, 2006
  4. No break over ssh to sun server

    , Mar 9, 2006, in forum: Computer Support
    Replies:
    1
    Views:
    472
  5. John Heitmuller
    Replies:
    1
    Views:
    774
    Doug McIntyre
    Apr 22, 2008
Loading...

Share This Page