General Questions

I have a small company with 15 or so machines running Windows 2003 Server using Active Directory.  I was previously using a Sonicwall TZ170.  I replaced the Sonicwall with a Generic PC image of M0n0wall build 1.3.

Everything works fine exceptsome pages such as Yahoo.com or CNN.com will not come up.  I get a 'Page Not Displayed' error message.  I put the Sonicwall TZ170 back in place and the websites come up with no problems.

I looked over all the documentation, but have not found any information or posting with anyone having a similar issue.

I love the ability of the M0n0wall and really need your assistance in troubleshooting this issue.

Thanks for your time and any help you guys provide me.

Bigraz

Hi,

I am using v1.3b4, and have no problems in openning the both sites you mentionned.... Maybe something is wrong at your ISP ?

What kind of error is your browser reporting ?

Sounds like a typical MTU issue. What's your WAN MTU and what kind of connection is it?

I upgraded to 1.3b4 and the problem still exists.  I receive 'Page Not Displayed' error message.  My Sonicwall has no such issues that I'm having with the M0n0wall. 

I have Comcast Cable 8MB down /512 up connection.

How do I troubleshoot the MTU?  I have not changed anything on the OS level.  I believe the MTU on the WAN is 1500.

Yes, cable should be 1500 and if you haven't entered anything on the WAN page it will be. Is the MTU on your LAN also 1500? (i.e. no gigE with jumbo frames or anything)

I don't think I've ever seen this being a problem with 1500 MTU connections, generally it's specific to PPPoE. Definitely sounds like that's the issue though.

Thanks cmb for the replies.

I downloaded a program just to verify what my MTU and it was confirmed 1500.  I setup up my Sonicwall just to see if the sites worked and they pulled up no problems.

Do you have any other suggestions on what to try next.

At this point it will be very difficult to figure out exactly what's happening without packet captures. Do you have a managed switch where you can configure a SPAN port, or a hub you can drop in temporarily to capture traffic?  Ideally what you need is a box with two interfaces that can monitor LAN and WAN simultaneously and write the captures out to a file. Then analyze them to see what's happening. If you aren't familiar with analyzing capture files, you can email them to me and I'll take a look. If you need further instruction, post back.

I didn't read through all the replys, but if you are running a router behind your monowall, make sure NAT is disabled.  Just a thought.  Good luck.