Home page intermittantly disappearing

[Kesser]

I have a corporate user who has a website which thier business relys on. Often they, (the user) cannot access thier website although the rest of the world can...

The site is written by a third party in PHP and the network is protected by a hardware firewall on a DLINK router.

Advise taken by a network specialist suggests a regular hacking attempt, I don;t know enough to disagree but my gut feeling says no...

The problem is very intermittant, it may happen twice in one week and then go away for three, resetting the router has solved the problem on a number of occasions which suggests to me that it is a prob with the firewall and setting up of - the router has a browser interface where you can configure but much of it is dutch to me.

Does anyone have any suggestions that may help or is there something obvious that i am missing?

Ta

Kes

 

[mattjurado]

Often they, (the user) cannot access thier website although the rest of the world can..."

Okay, couple of questions.

1. Does the web server hosting the page respond to pings?
2. If so, can they ping the server by ip address when the problem occurs?
3. If so, can they ping the server by domain name when the problem occurs?
4. Does the DLink really have a firewall function, or are you just using the term because it sits in front of the network, acting as a firewall in a physical sense?
5. Maybe this should have been the first question, but when did this start? Were things ever okay with the DLink in place?
6. Another question out of order, what exactly does their web browser say when this happens?
7. Have you simply tried emptying the browser cache on the desktop?

You may not have answers to all of these, but record them next time it happens, it will help reveal the source. Could be the DLink, but I am betting its not.

Matt J.

Please always take the time to backup any and all data before performing any actions suggested for ANY problem, regardless of how minor a change it might seem. Also test the backup to make sure it is intact.

 

[Kesser]

Hi Matt,

Yes - all ping requests are answered..

The Dlink router has a built in hardware firewall is my understanding

This started after the user changed thier dommain name and web server - i asked them to check this out with the person who deals with the site but i think he is better on databases and the site is a 'click and build' through global webstore.

I empty all caches once a week...........

does this mean any more to you?

Kes

 

[PaulTEG]

Kes,

how are you pinging it, by IP, or hostname?
If it answers IP, and not host it looks like it might be a DNS issue in that the ISP is reloading the DNS servers at the same time that the client is accessing his site.

This happens regularly in Ireland, and is why you're supposed to specify a secondary DNS server

What model of D-Link router?

You could look for, and deploy, more responsible DNS servers, and see if that answers the problem

Look for reviews of his ISP, and see what sort of rep they have, you could recommend a better option, resell it and take a cut, say 10% - remember clients only get what they pay for.

HTH
--Paul

It's important in life to always strike a happy medium, so if you see someone with a crystal ball, and a smile on their face ... smack the fecker

 

[smah]

I'm thinking along the same lines as PaulTEG. I'm guessing that the web server is on the local network behind the D-Link router. My thinking is that the 'loopback' feature of the router is getting confused/acting up or otherwise not playing nice for some reason. When this next happens, try this before you reboot the router: try connecting to the webserver using it's local (private range) network address - something like

http://192.168.0.XXX

If this works, then the problem is with the router loopback function and it can be overcome with a simple hosts file.

 

[Kesser]

Hi & thanks

Yes I think I pinged by IP not host name - this is all getting out of my range of expertise......

I will try that next time it happens but how do I create a host file if that proves to be the problem?

Also I will look into the isp as it seems odd to me that this only happened since they changed to a 'faster' server..

thanks guys, i'll keep you informed...

 

[Kesser]

Hi all and thanks for previous advise - the problem is still occuring and it would seem that the router is losing it's settings completely now following a loss of the home page.

I stipulate that I am a novice in this area, so be gentle with explainations please...

The LAN was set up to 'obtain ip automatically' - the person I paid to set up the network told me it had been done by ip address stipulated and even gave me a list of ip addresses for the machines... will this make a dif? I have been told that because of the way the router works, it's losing the dhcp settings as they are not being refreshed as they are dynamic...? I noticed today that the router could not 'see' an ip at all for the internet - I have redone the network with an ip specified on each machine and also specified dns range as obtained from the isp in the hope that this will work.

The comment above about loopback makes sense to me but how to go about it i don't know....

The router is a DLINK DSL 504 - I also downloaded the latest firmware today but have not installed as I wanted to see what the network lchanges did first..

Any further advice would be much appreciated....

Kes

 

[mattjurado]

Post back, I suspect you are on the right track. For smaller organizations, static ips on the desktops is really the way to go. I see way too many weird issues with dhcp, this could be one of them.

The other high probability is the DLink itself. If the latest firmware doesn't help, just go get a Linksys router. Just as easy to setup.

Matt J.

Please always take the time to backup any and all data before performing any actions suggested for ANY problem, regardless of how minor a change it might seem. Also test the backup to make sure it is intact.

 

[Kesser]

Thanks matt, will do.... feedback is helpful when it's new....

Kes