Why is there a delay with no shut command on a serial interface?

JockVSJockJockVSJock Member Posts: 1,118
in CCNA & CCENT
So yesterday I was troubleshooting an issue with a distant end and had to change the interface (from shut to no shut) and protocol (ppp to hdlc) on a serial interface on a Tier 2 Cisco Router.

I was under the gun and for some reason it seems like I waited a few minutes when waiting to see that glorious up/up on that Serial Interface.

Chris Bryant talked about this on his Train Signal DVD. If you change the open/close the interface and/or change the protocol, stick around a few minutes to confirm that it is correct. However he didn't go into the why. I Googled around and couldn't find an answer and was wondering if anyone knew why there is some time delay with this.

thanks
***Freedom of Speech, Just Watch What You Say*** Example, Beware of CompTIA Certs (Deleted From Google Cached)

"Its easier to deceive the masses then to convince the masses that they have been deceived."
-unknown
· Share on FacebookShare on Twitter

Comments

  • ciscoman2012ciscoman2012 Member Posts: 313
    Hmm I would like to know the answer too.

    The only thing I know is that Chris Bryant is the sh!t
    · Share on FacebookShare on Twitter
  • ChickenNuggetzChickenNuggetz Member Posts: 284
    JockVSJock wrote: »
    So yesterday I was troubleshooting an issue with a distant end and had to change the interface (from shut to no shut) and protocol (ppp to hdlc) on a serial interface on a Tier 2 Cisco Router.

    I was under the gun and for some reason it seems like I waited a few minutes when waiting to see that glorious up/up on that Serial Interface.

    Chris Bryant talked about this on his Train Signal DVD. If you change the open/close the interface and/or change the protocol, stick around a few minutes to confirm that it is correct. However he didn't go into the why. I Googled around and couldn't find an answer and was wondering if anyone knew why there is some time delay with this.

    thanks

    I'm assuming this was a lab set-up that you're playing around with. If it is, the delay could be on account of the DTE/DCE clock rates synchronizing.
    :study: Currently Reading: Red Hat Certified Systems Administrator and Engineer by Ashgar Ghori

    Certifications: CCENT; CCNA: R&S; Security+

    Next up: RHCSA
    · Share on FacebookShare on Twitter
  • JockVSJockJockVSJock Member Posts: 1,118
    ChickenNuggetz wrote: »
    I'm assuming this was a lab set-up that you're playing around with.

    This is actual production equipment.
    ***Freedom of Speech, Just Watch What You Say*** Example, Beware of CompTIA Certs (Deleted From Google Cached)

    "Its easier to deceive the masses then to convince the masses that they have been deceived."
    -unknown
    · Share on FacebookShare on Twitter
Sign In or Register to comment.