Koozali.org: home of the SME Server

Legacy Forums => Experienced User Forum => Topic started by: Jáder on July 26, 2005, 04:18:39 PM

Title: Internet access problem
Post by: Jáder on July 26, 2005, 04:18:39 PM

Hi,

I had a server in server-gateway public mode (2 NICs).
After some clients complains, I decided to remove one NIC from server, and redirect all internet to firewall directly. So now SME is as server only.
That would allow a quicker internet access and  lower load on main server.

BUT... after that, very often the network get without internet access.
I removed firewall and let connection go directly to ADSL modem... but still getting "blanks time" without internet.

The problem appears after a certain amount of users connect to internet.

There is a manageable switch on this server. But not all clients connect thru it... there are some cascade switches! :(

I discovered that when the LAN has no access to internet, webmail on main server still works.
All the time, an ACCESS application (main application of this client... PLEASE don´t ask!!) still works very quick.

Any tips?

Thanks

Jáder

Title: Internet access problem
Post by: brianr on July 26, 2005, 05:22:27 PM

Jader I would look closely at your internet gateway device (the ADSL router), it is unlikely to be a problem with the SME Server, especially as you say that the webmail and the Access application still runs well.

The problem might even be "past" the router, and be some traffic isssue at the ISP.  

cheers

Brian

Title: Internet access problem
Post by: Jáder on July 27, 2005, 07:38:36 PM

Brian

I have done a VERY CLOSE look at ADSL router.
I mirror the ADSL port to another one in switch and do a packet capture in moments without web.
I discovered just a few packets arrived to ADSL router when "no internet"... even if I try to access.
I did the capture with Ethereal!
BUT by now this client will get a new adsl link (a second one!)... so will wait to watch how this new link will "affect" my problem!

Jáder

Title: Internet access problem
Post by: kruhm on July 31, 2005, 02:07:41 PM

i get blasted everytime i recommend this but...

In my experience, when sme runs in server-only mode you have to set the external dns option in the panel for it to work correctly.

Title: Internet access problem
Post by: Jáder on July 31, 2005, 04:40:18 PM

I appreciate your help... no flames from me :)

I´m sure that could solve some problems... I use to put an external DNS (from a BIG ISP) as secondary, for DHCPd  (using Advanced Workgroup addon) and for server.

But this is far beyond that... even ping to an IP address do not go! Even ping to firewall/router internal NIC don´t get any answer!

The problem is related to amount of machines.
We return to put NO gateway on DHCP and set manual IP/DNS/gateway to computer with Internet access... it´s working.
So the problem is one of these:
1) a computer randomly generating spurious net traffic and jamming firewall/router internal NIC
2) too many computer in local network to this router (it´s a DSL 500G).

Any help it´s welcome!

Thanks

Jáder