Fixing Nortel Contivity Client VPN issue: Login failure due to remote host not responding

I have been receiving this error for a few days now fueling my laziness to connect at the office. But unfortunately last week I was asked to assist in implementing a major change so I need to connect from home prompting me to fix this issue or else I need wake up early and haul my *ss to the office on a weekend.

The setup is I connect to the office VPN via the Nortel Contivity client utilizing SecureID token. I keep getting the error “Login failure due to remote host not responding” when I tried to connect. I didn’t have this problem before and can connect from my “virtualized” laptop (I did a Physical-to-Virtual (p2v) migration of my office laptop so that I don’t have to bring the laptop home often).

Going through the Nortel Contivity Client document, I found this:

This is typically caused by UDP500 traffic not getting back to the requesting client through a firewall and/or router.  If your firewall/router supports IPSec passthrough you must enable IP50, IP51, UDP500 on both the source and destination (i.e. bidirectional) in order for the client to establish the connection.  Some firewalls/routers have a generic setting "Enable IPSec" or "Enable IPSec Passthrough" and simply turning this on will usually solve the problem.

The keyword here is IPSec Passthrough. In order for IPsec to work through a NAT, the following protocols need to be allowed on the firewall:

  • Internet Key Exchange (IKE) – User Datagram Protocol (UDP) port 500
  • Encapsulating Security Payload (ESP) – IP protocol number 50
  • Authentication Header (AH) – IP protocol number 51

I immediately login to my router administration panel and there it is, the IPSec Passthrough was disabled.  This might have been disabled after a recent upgrade of the router’s firmware. After enabling this feature, the VPN client connected immediately.

DD-WRT –> Security -> VPN Passthrough

By the way, I have a Linksys WRT320N using a third-party firmware called DD-WRT.

image

Enhanced by Zemanta

1,212 Comments

  1. ptcopener.com

    Howdy! I could have sworn I’ve been to this website before but after
    reading through some of the post I realized it’s new to me.
    Anyways, I’m definitely delighted I found it and I’ll be bookmarking and checking back
    frequently!

    Reply
  2. Laurene

    Heya i am for the first time here. I found this board and I to find It really helpful & it helped
    me out a lot. I am hoping to offer something again and help others like you helped me.

    Reply
  3. Kit

    It’s in fact very difficult in this busy life to listen news on TV, therefore I simply use internet for that
    purpose, and take the hottest information.

    Reply
  4. zhongguoxihua.com

    We are a group of volunteers and starting a new scheme in our community.

    Your web site provided us with useful info to work on. You’ve done an impressive activity and our whole neighborhood will
    probably be thankful to you.

    Reply
  5. Barrett

    Wow that was unusual. I just wrote an extremely long comment but after I clicked submit my comment didn’t appear.
    Grrrr… well I’m not writing all that over again. Regardless,
    just wanted to say wonderful blog!

    Reply
  6. ??-?????.xn--p1ai

    I know this site offers quality based content and other data, is there
    any other web site which presents these kinds of stuff in quality?

    Reply
  7. http://stage.kashmirawareness.org/

    Hello this is kind of of off topic but I was wondering
    if blogs use WYSIWYG editors or if you have to manually code with HTML.
    I’m starting a blog soon but have no coding skills so
    I wanted to get guidance from someone with experience.
    Any help would be enormously appreciated!

    Reply
  8. Elouise

    Thank you for the good writeup. It in reality was a amusement account it.
    Glance advanced to more introduced agreeable from you! By the way, how can we keep in touch?

    Reply
  9. Suzanna

    I’d like to find out more? I’d care to find out more details.

    Reply
  10. Pingback: best wedding photographer chandigarh

  11. Kirsten

    Hey there! Do you know if they make any plugins to assist with SEO?
    I’m trying to get my blog to rank for some targeted keywords but
    I’m not seeing very good results. If you know of
    any please share. Many thanks!

    Reply
  12. Lelio Vieira Carneiro Junior

    Howdy just wanted to give you a quick heads up.
    The words in your post seem to be running off the screen in Safari.
    I’m not sure if this is a format issue or something to do with browser compatibility
    but I figured I’d post to let you know. The design look great though!
    Hope you get the problem fixed soon. Kudos

    Reply

Leave a Comment

Your email address will not be published. Required fields are marked *