Hot Downloads

Welcome, Guest
Username: Password: Remember me
  • Page:
  • 1

TOPIC: Bizarre Cisco 1841 DNS problem

Bizarre Cisco 1841 DNS problem 11 years 10 months ago #16232

  • LeeB
  • LeeB's Avatar Topic Author
  • Offline
  • New Member
  • New Member
  • Posts: 1
  • Thank you received: 0
Hi all, hopefully I'm posting this in the right forum :)

One of our servers (W2K) internet access stopped working sometime during the last 3 weeks. First I thought it was because DNS wasn't getting replies. I put some ACL rules in the two routers to Permit UDP:domain trafic and log it to the Linux box(network router). I was able to see DNS traffic on my machine (same sub-net) go out and come back. On the server DNS only seemed to go out and not come back.

Well the upshot of all this is that if I turn OFF the logging for the ACL rule, then this one machine suddenly starts getting DNS out and back. No other systems are effected. I don't understand how turning logging on or off should effect anything.

Web traffic doesn't work for this one server either.

The basic configuration is everything goes through a Linux box for routing/firewall, from there into a Cisco 1841 router, down a T1, into another Cisco 1841 router, then to a DSL router.

Any clues? I've read the online help, but it's not helpful enough. Any suggestions would be most welcomed.

Thanks,
Lee

Please Log in to join the conversation.

  • Page:
  • 1
Time to create page: 0.125 seconds

CCENT/CCNA

Cisco Routers

  • SSL WebVPN
  • Securing Routers
  • Policy Based Routing
  • Router on-a-Stick

VPN Security

  • Understand DMVPN
  • GRE/IPSec Configuration
  • Site-to-Site IPSec VPN
  • IPSec Modes

Cisco Help

  • VPN Client Windows 8
  • VPN Client Windows 7
  • CCP Display Problem
  • Cisco Support App.

Windows 2012

  • New Features
  • Licensing
  • Hyper-V / VDI
  • Install Hyper-V

Linux

  • File Permissions
  • Webmin
  • Groups - Users
  • Samba Setup