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Old 04-05-2005, 02:07 PM   #1
eldoran
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Registered: Apr 2005
Location: Black Hawk, Colorado
Distribution: Ubuntu
Posts: 26

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Can't access my apache2 webserver using external address from LAN


Ok - I'll do my best to explain my situation.

I have an apache2 webserver running on SuSE 9.1 -- Up until last week, I was able to access my webserver from my internal network using it's external address. My external IP address is 67.106.41.26 .. I could also access my webserver using it's internal address (192.168.22.5). Starting last week, any attempt to reach 67.106.41.26 from within my internal network times out. Everyone else in the world can get to that address but my internal network ;-) I can still access my server fine using it's internal address..

Here's what I see in logs:

- Going to internal address (192.168.22.5) - /var/log/messages shows me coming in . /var/log/apache2/access_log shows a page being served. Cool.

- Going to external address (67.106.41.26) - /var/log/messages shows me coming in (although from 67.106.41.16, which is the IP I look like to the rest of the world). /var/log/apache2/access_log show NOTHING! error_log shows NOTHING. It's as if my packet came in and didn't go anywhere.

This is really confounding me and my ISP provider (who's been working with me on this since it started happening).

I have links to some tcpdump output I could share, but since this is my first post, it won't let me include urls. Let's just say you can go to my IP address (67.106.41.26) and add /cgi-bin/external and /cgi-bin/internal to it to see both my failing (external) and working (internal) tcpdump output.

I don't really know how to interpret tcpdump output - but they look wildly different.

Can anyone help me understand what I might do to determine where the problem is? I suspect my ISP's routing... I had not touched my webserver in weeks and this just started happening... but I'd like some more definitive data to help troubleshoot this.

Any input would really be appreciated. If I can provide any more explanation or data, please let me know! Thanks all!!
 
Old 04-05-2005, 02:09 PM   #2
masand
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Registered: May 2003
Location: INDIA
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hi there

what do u get

traceroute 67.106.41.26

regards
 
Old 04-05-2005, 02:37 PM   #3
benjithegreat98
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Registered: Dec 2003
Location: Shelbyville, TN, USA
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Have you made any changes to your gateway or router lately? That is usually what allows you to use a public IP in your LAN. Most small router (like a linksys) allow you to use the public IP in the LAN. A lot of real routers/firewalls (over $1000) do not allow this. To compensate you would use an internal DNS server. Like where I am www.hostname.com has a real world DNS entry to a public IP, but we also have an internal DNS server where it resolves to 10.11.12.2 (an internal IP address).
 
Old 04-05-2005, 03:43 PM   #4
eldoran
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Registered: Apr 2005
Location: Black Hawk, Colorado
Distribution: Ubuntu
Posts: 26

Original Poster
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traceroute 67.106.41.26 just shows my router (192.168.22.1) as the first hop and then a bunch of asterisks..

I have made changes to my router since this started happening (upgraded firmware, tried static routes, etc) --- but I had made none before this started. I have a Linksys, and it seemed to work just fine... though I've tried changing lots of settings to get things to work, it is set back to the way it was initially.

What bugs me is seeing the packet come in ... but then nothing happening! If it comes from my internal network - I show up in apache logs. If I come from external - the packet gets to my server and is accepted, but nothing shows up in the apache logs.

What would cause a packet to show up - bound for port 80 -- but not get passed to Apache? That's what's throwing me here....

Thanks for your responses!
 
Old 04-05-2005, 11:10 PM   #5
masand
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Location: INDIA
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the problem can be if there is no gateway specified for this ip address in the router

can u give a list of getways defined on your router

try

route -n

regards
 
Old 04-05-2005, 11:22 PM   #6
eldoran
LQ Newbie
 
Registered: Apr 2005
Location: Black Hawk, Colorado
Distribution: Ubuntu
Posts: 26

Original Poster
Rep: Reputation: 15
My routing is pretty normal -- and all looks good..

Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
192.168.22.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0
169.254.0.0 0.0.0.0 255.255.0.0 U 0 0 0 eth0
127.0.0.0 0.0.0.0 255.0.0.0 U 0 0 0 lo
0.0.0.0 192.168.22.1 0.0.0.0 UG 0 0 0 eth0

(I think the 169.254.0.0 one is for Samba)

I also think we've found a clue that points at my ISP's router...

I am seeing my packets come in from 67.106.41.16 when I hit my server with the external address.. when actually my IP address is 67.106.41.26 (my first post was wrong about this -- I should be .26). Why I am showing up as 67.107.41.16 only when I go out and come back in is a mystery - but it's led me to believe this is not 'my' problem. My ISP guy tells me that .16 is actually the address of the router used to route traffic in my area... so somehow my static IP address is getting lost when I go out and come back in, and I'm showing up as the address of my ISP router!

When I pointed all this out to my ISP guy - he got excited and was off to call his router tech support... I'm hoping this gets resolved on his end. Will let you know. Thanks!!

Last edited by eldoran; 04-05-2005 at 11:23 PM.
 
Old 10-26-2008, 03:51 PM   #7
soccrstar
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Registered: Oct 2008
Posts: 1

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Quote:
Originally Posted by benjithegreat98 View Post
Have you made any changes to your gateway or router lately? That is usually what allows you to use a public IP in your LAN. Most small router (like a linksys) allow you to use the public IP in the LAN. A lot of real routers/firewalls (over $1000) do not allow this. To compensate you would use an internal DNS server. Like where I am has a real world DNS entry to a public IP, but we also have an internal DNS server where it resolves to 10.11.12.2 (an internal IP address).
Thank You so much

You helped me solve this issue

I too was having issues with apache2 not working outside my lan. I am behind my router. I had to let my router know WHERE my webserver was. fixed the settings on my router and boom I can access it outside lan. WoHOO..

It was under the settings called. "Virtual Server"
 
  


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