First of all I have looked elsewhere on the forum and (unless I have missed it) I couldn't find any prevoius mentions of my type of problem.
Forgive me if this is not the case.

I have a Netgear DG834GT router connected to my ISP (Orange in France). Connected to it I have 1 PC on LAN A and 1 Server on the same LAN A. The server is also on LAN B (2 NIC's in the server). The LAN B card on the server is connected to a switch which has 3 other PC's connected to it. The server is running Small Business Server 2003 with a DNS Server, ISA server and IIS Server. The IP configuration is:

Router:

  • PPPoA connection at 16Mb.
  • Dynamic IP address. (soon to be fixed)
  • NAT on.
  • MTU 1500.
  • LAN assigned IP address: 172.16.0.1
  • NetMask: 255 255.000.000
  • DHCP on - IP Range 172.16.0.10- to 172.16.0.20
  • RIP direction: Both.
  • No Static Routes defined
  • Firewall Rules: Various inbound, to allow services through to Server.

PC on LAN A:
Windows IP Configuration
Host Name . . . . . . . . . . . . : AL1
Primary Dns Suffix . . . . . . . :
Node Type . . . . . . . . . . . . : Unknown
IP Routing Enabled. . . . . . . . : No
WINS Proxy Enabled. . . . . . . . : No

PC NIC on Lan A:
Ethernet adapter Wired Ethernet Network:
Connection-specific DNS Suffix . :
Description . . . . . . . . : NVIDIA nForce MCP Networking Adapter
Physical Address. . . . . . . . . : 00-50-8D-F3-9A-23
Dhcp Enabled. . . . . . . . . . . : Yes
Autoconfiguration Enabled . . . . : Yes
IP Address. . . . . . . . . . . . : 172.16.0.10
Subnet Mask . . . . . . . . . . . : 255.255.0.0
Default Gateway . . . . . . . . . : 172.16.0.1
DHCP Server . . . . . . . . . . . : 172.16.0.1
DNS Servers . . . . . . . . . . . : 172.16.0.1

Server:
Windows IP Configuration
Host Name . . . . . . . . . . . . : acme
Primary Dns Suffix . . . . . . . : acme.local

Node Type . . . . . . . . . . . . : Unknown

IP Routing Enabled. . . . . . . . : No

WINS Proxy Enabled. . . . . . . . : Yes

DNS Suffix Search List. . . . . . : acme.local

Server NIC on LAN A:
Ethernet adapter Internet Connection:
Connection-specific DNS Suffix . :
Description . . . . .. . : Intel(R) PRO/1000 MT Network Connection
Physical Address. . . . . . . . . : 00-14-22-4D-19-F9
DHCP Enabled. . . . . . . . . . . : No
IP Address. . . . . . . . . . . . : 172.16.0.2
Subnet Mask . . . . . . . . . . . : 255.255.0.0
Default Gateway . . . . . . . . . : 172.16.0.1
DNS Servers . . . . . . . . . . . : 192.168.16.2
NetBIOS over Tcpip. . . . . . . . : Disabled

Server NIC on LAN B:
Ethernet adapter Local Area Network Connection:
Connection-specific DNS Suffix . :
Description . . . . . . . . . : Intel(R) PRO/1000 MT Server Adapter
Physical Address. . . . . . . . . : 00-0E-0C-A9-B5-9E
DHCP Enabled. . . . . . . . . . . : No
IP Address. . . . . . . . . . . . : 192.168.16.2
Subnet Mask . . . . . . . . . . . : 255.255.255.0
Default Gateway . . . . . . . . . :
DNS Servers . . . . . . . . . . . : 192.168.16.2
Primary WINS Server . . . . . . . : 192.168.16.2

Sample PC on LAN B:
Windows IP Configuration
Host Name . . . . . . . . . . . . : PC2-AL
Primary Dns Suffix . . . . . . . : acme.local
Node Type . . . . . . . . . . . . : Hybrid
IP Routing Enabled. . . . . . . . : No
WINS Proxy Enabled. . . . . . . . : No
DNS Suffix Search List. . . . . . : acme.local

SAMPLE PC NIC on LAN B:
Ethernet adapter Local Area Connection:
Connection-specific DNS Suffix . : Piscine-PlusCom.local
Description . . . . . . . . . . . : VIA Rhine II Fast Ethernet Adapter
Physical Address. . . . . . . . . : 00-40-CA-8B-51-B7
Dhcp Enabled. . . . . . . . . . . : Yes
Autoconfiguration Enabled . . . . : Yes
IP Address. . . . . . . . . . . . : 192.168.16.20
Subnet Mask . . . . . . . . . . . : 255.255.255.0
Default Gateway . . . . . . . . . : 192.168.16.2
DHCP Server . . . . . . . . . . . : 192.168.16.2
DNS Servers . . . . . . . . . . . : 192.168.16.2
Primary WINS Server . . . . . . . : 192.168.16.2

Now, for my problems!!

Sometimes I am getting no connection from my PC's on Lan A or B to the Internet. On further inspection it is often the router loosing its connection to the ISP, sometimes the switch, sometimes the NIC's in the PC's; or maybe its coincidence that when resetting one or more of these the problem usually goes away.

When I do have a connection to the Internet, the router is often reporting it at less than the 16Mb that I should have; Sometimes as low as 12Mb. I have tried playing with the MTU on the router to no significant effect. The ISP will not tell me the optimal value. (Partly a language problem).

Mt gut feeling is that it is a problem to do with (lack of static) routing and DNS, but for no particular reason.

Can anyone tell me if there is anything that it obviously wrong with my IP settings anywhere.

Greatly appreciated.

A little bit of extra info; the http requests seem to be succesful (so DNS is working) but it's the replies that don't seem to get back.

Andy

Now I am confused - have I posted this correctly.? Doesn't anyone have any idea?

Be a part of the DaniWeb community

We're a friendly, industry-focused community of developers, IT pros, digital marketers, and technology enthusiasts meeting, networking, learning, and sharing knowledge.