Hi all,

I have installed a new 3Com wireless Officeconnect 3CRWE554G72T router
in my home last month,
(for 4 computers, only 1 is wireless).
A strange phenomenon has emereged, where although most surfing works
fine on all PC's, some internet sites refuse to load on all of them, I
am guessing due to DNS resolution problems.

I have the Router set up with DHCP, the PC's set up with static IPs,
and the router dials up to my Cable provider with an L2TP VPN dial
tunnel (thats the config of this provider). Some particular sites such
as mail.lycos.com only load on some days, on others there is a blank
page when entering the URL and then just "Opening page.." at the bottom
of IE, and after about a minute: The page cannot be displayed.

I think its a DNS problem because I have ruled out most of everything
else. When I dial up to the internet using the pre-router method,
i.e. reconnecting the cable modem to the PC and using a Win2k VPN dial
up, it works flawlessly to the same sites which the router stalled 30
seconds before (so it couldn't be their server is down or something)

I have tried the same DNS server config (automatic)
on both the router and old VPN connection, to no avail.
I have also tried to set up the DNS servers manually in the Router
config screen and the win2k network connection, with 192.168.1.1 as the
DNS server in win2k, and also manually setting the DNS servers in
win2k.

I have also tried deleting Windows 2k and reinstalling it.
I use Win2k/SP4, IE6 SP1 with all updates, tried many spyware scanners
(which is not the problem, if it were, how come it does work when
bypassing the router on the same PC and browser?) simlarly if it was a
weak DNS server, how come it works fine with the L2TP direct connection
without the router...?

I have also tried ipconfig /renew, /release, /flushdns etc.


Thank you for any help

On 27 Jan 2006 07:28:34 -0800, developmental2@walla.com wrote:

You check this by trying the IP address of a site and the hostname, you
mentioned lycos below so try,

Generally you try something like,
http://mail.lycos.com
or
http://208.36.123.66/
or
http://208.36.123.67
except I get an error for the last 2, they know the difference between
the name / numeric access.

In that case
http://www.ibm.com
or
http://129.42.21.99
http://129.42.16.99
http://129.42.17.99
http://129.42.18.99
http://129.42.19.99
http://129.42.20.99


You can convert names to numbers using www.dnsstuff.com and that's
http://66.36.247.82/


That's to accept DHCP from the ISP.

PCs on static because?

That's the reason for the static addresses?

This may also be a proxy server issue if you have that set in Tools /
Internet Options / Connections / Lan Settings

You may have issues resolving this name in the setup you have. If your
ISP doesn't need a proxy, try without an entry. Or change the proxy name
to the IP address.

How about mail , news other apps, there is the same DNS issues?

In that case you need to compare the output of

ipconfig/all

in your 2 configs.

You can save the output to a file

ipconfig/all > filename.txt

To get the settings from where?

Manually pointing to where?

Which PC is 192.168.1.1 , one of yours? Then are you running a DNS
server on your LAN?

To what settings?

That's not the issue.

If that's from the PCs , that you set to static IP's then renew and
release won't do anything.

Only flushdns which clears the local cache entries may sometimes help.

You seem to be misunderstanding the most basic way ISP to PC setup
works. Generally, (assuming an DHCP setup all the way)


ISP , sends DHCP settings IP address / DNS server to a PC. The PC is set
obtain an address / DNS settings automatically.
These settings are the IP address the ISP gives your PC, the DNS server
addresses of the ISP.

If you use -
ISP - Router - PC

The router accepts the same DHCP settings internally from the ISP, it's
now actings as the PC did.
Your PC then gets an IP from the router on it's internal range , but
passes on either ISP DNS settings or if the router has a built in DNS it
tells the PC the DNS is itself.

When you need to resolve mail.lycos.com , the PC asks the router, the
router asks the ISP , etc.

If you set the PC to static addresses ( I usually manually configure the
DNS settings to the ISP , or my DNS server or the router. Not something
that usually should be attempted. Because my ISP uses DHCP and the
IP/DNS settings are subject to change. ) you need to make sure the
manually configured settings are the same values from the output of...

ipconfig / all

....if you are using the router or non router configuration.

There is on Windows , and many other systems a command line utility
called nslookup.

Open a CMD prompt.
type 'nslookup' without the '' you see somrthing like, I haven't names
my server henxe the UnKnown.

C:\temp>nslookup
Default Server: UnKnown
Address: 192.168.0.1


At the > prompt you type either the URL mail.lycos.com or the IP
address and press enter. Resulting in -


Address: 192.168.0.1

Non-authoritative answer:
Name: mail.lycos.com
Addresses: 208.36.123.66, 208.36.123.67



Or OTOH


Address: 192.168.0.1

Name: http7-1.us4.outblaze.com
Address: 208.36.123.66

To exit nslookup ,

Press enter.


The UnKnown server address is the DNS in my router, the router config
page also lets me view the ISP DHCP configured settings.

I could check the ISP supplied values and manually configure the PCs to
use those values for DNS. Which Win NT4/2000/XP lets you do even if you
are using DHCP from the router (i.e. not using the router DNS) or static
ISP addresses. Or your router may even allow you to disable it'sinternal
DNS and use the ISP DNS.

You really need to check as mentioned the output of

ipconfig/all , using the router or not.


Me

Thank you for your detailed reply.


I have Now noticed that the problematic PC has "enable lmhosts lookup"
disabled,
all the others are enabled.
I enabled it and then internet browsing resumed (even to lycos mail)
[note: I have a lmhosts file in each PC with IP's of all the other
local computers].
by the way my localhost file is also set to 127.0.0.1, and forgot to
mention, sorry,
its a peer to peer network without a domain, all PC's set to same
workgroup.


I'm still suspicious that the LMHOSTS is only a temporary solution and
the problem still lies in some misconfiguration in my network due to my
ignorance of networking.


because, I was advised that it provides faster browsing than relying on
DHCP. DHCP is still enabled on the router, but I don't use it, since
the PC's are statically configured. (Except one laptop which has
"automatic" detection enabled so it can roam to other (public) wireless
networks without bothering the network admin (yours truly..)

Well I have no proxy that I know of, never had (even before I had the
router).
All options in LAN settings are empty and checkmarks are not checked


well as far as I understand it (and I am admittedly new to this) I have
DHCP enabled and my ISP's DNS servers defined in the router config
screen, so if I switch the PC's to automatic settings, they should get
these settings from the router.

configured,
If I do an Ipconfig /release, internet stops, and resumes when I do an
Ipconfig /renew
perhaps my network settings are so messed up that its not really
statically configured and I only think it so, donnu.

The router doesn't have a DNS server as far as I know.
192.168.1.1 is my router address which is also the gateway as far as I
understand.
all of the PC's are configured with ip addresses in the range the
router allocated.

I forgot to mention I have a netbeui protocol for the local file
sharing network, since I was advised it is safer than sharing it over
tcp/ip. (I don't need access to the network over remote connections,
all of the pc's are in the same location).

Also, When I try a:
C:\>ipconfig /renew *Local* (the LAN adapter shows up as "Local Area
Connection")
on the faulty computer, it results in:

Windows 2000 IP Configuration

Error: No adapters bound to TCP/IP are enabled for DHCP

But when I try the same command on the adjacent computer (which is
connected to ther same LAN and also has identical configuration, other
than its different IP)

there is no error, but the command returns to the prompt without any
further messages
(I assume that means it completed).

Nslookup:
I tried your suggestion. When I type it, it doesn't result with "Server
unknown" and 192.168.0.1 (or in my case 192.168.1.1, my router's
address) as in your example, but responds with my ISP's server address
and the IP it assigns to the dial up connection. (I don't have a
permanent lease, so it changes every connect). is that good or bad?
when I try nslookup with a web site URL it works and responds with its
IP, but I suspect that's only since I added the LMHOSTS import
checkmark.

perhaps I should disable DHCP on the router and revert to all static
setup on my network..?

I am also considering installing a third party DNS server such as
treewalk (already tried fastcache and it didn't help). But I firmly
believe it is some simple setting somewhere that's wrong.

Thank you so much again for your time in reading my message!

On 28 Jan 2006 09:00:03 -0800, developmental2@walla.com wrote:

lmhosts file went out with the Dodo.

If you really have to , you want to use the hosts file.

There is always a 127.0.0.1 default entry.

You don't want any external sites in 'lm'hosts files(s), although in
some cases it's used for ad blocking, preventing access to some sites.

I never use the local files even for the servers on my LAN I manage
without. All external name resolution is through the router DNS or ISP
DNS, or when using ExtraDNS or a Linux DNS then it looks up multiple
external sources.

Correct, don't use lmhosts anywhere.

DHCP is only the provision of automatic settings. Once those settings
are obtained by a system , it's the DNS , (WINS) , time server or other
settings that are used.

Never had any issues with the 1800 PCs at work with that.

It happens.

Yes, if the PCs use DHCP to obtin the settings. In the case on 2000/XP
you can set - user static IP and DNS obtain automatically.

That's what the output of ipconfig/all and the options in Internet
Protocol / Properties tell you.

Haven't looked at the manual.

Yes.

I would hope so.

File , as long as it local connections.

Then it's a static IP that's been set, or a NIC driver / card fault.

Then you can check the output of ipconfig /all , it has 2 lines with the
date/time for lease obtained / expires.

I said it was *my setup* which did the "unknown", there are examples and
there are exact answers based on *your* setup.

Which is what a said, address of your router.

You can, I have a half and half. There are some servers on my setup so
these are static and the rest aren't.

After this conversation, that doesn't sound like a good idea.

Not only do you have to deal with the LAN side addresses, you have to
set forwarding (lookups) to the ISP or other external DNS servers.

Most often is.

YW.

Thanks-
then perhaps, since my problems are intermittent, they return every
time the lease expires
and are repaired by ipconfig /flushdns or /renew ?
that seems to be my experience in the last week or two.
My lmhosts file lists no external sites, only the ip's of the machines
on the local network.
Dodos or no, that's the only change I made and it seemd to fix
things..! thats all I could find before the users come flocking in
tomorra..

Regarding DNS capabilities of my router, I really don't think it has
any-even though it is listed
in the non-3com sales pitch specs,
I looked all over the 3COM specs, setup screens and user guide and
there's nothing about that, except "DDNS" tab which says :
Dynamic DNS provides users on the Internet a method to tie their domain
name(s) to computers or servers. DDNS allows your domain name to follow
your IP address automatically by having your DNS records changed when
your IP address changes
And this bit:
Robust Routing Features
IP routing (RIP 1 and 2) and static routing allow the router to be used
in multi-network
environments. Dynamic Domain Name Service (DNS) enables users
connecting to
the Internet with dynamic IP addresses to use network applications such
as Web or
FTP servers that normally require static IP addresses.

doesn't sound like it. Its only a low end wifi router.

here's the ipconfig /all on the "ill" machine (which seems to work ok
after the lmhosts inclusion, but web site lookup still is noticable
slower than the other machines even though they hare half as fast
CPU-wise..)

C:\>ipconfig /all

Windows 2000 IP Configuration

Host Name . . . . . . . . . . . . : xxxxx
Primary DNS Suffix . . . . . . . :
Node Type . . . . . . . . . . . . : Broadcast
IP Routing Enabled. . . . . . . . : No
WINS Proxy Enabled. . . . . . . . : No

Ethernet adapter xxxxxxxxxx

Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : Realtek RTL8139(A) PCI
Adapter
Physical Address. . . . . . . . . : 00xxxxxxxxxx
DHCP Enabled. . . . . . . . . . . : No
IP Address. . . . . . . . . . . . : 192xxxxxxxxx
Subnet Mask . . . . . . . . . . . : 255xxxxxxxxx
Default Gateway . . . . . . . . . : 192xxxxxxxxxx
DNS Servers . . . . . . . . . . . : 212xxxxxxxxxx
212xxxxxxxxxxx
NetBIOS over Tcpip. . . . . . . . : Disabled

Thanx again

On 28 Jan 2006 15:39:10 -0800, developmental2@walla.com wrote:

Which lease, from the ISP?

Or not the lease on the PC if you said the PC was set to static
addresses.

Usually that should be the job of a DNS server in the router.

The thing here is you have said only local machines are in the lmhosts
file, you enabled it and mail.lycos.com worked. That isn't right.

Then some thing else more basic is wrong and *needs* fixed for a
permanent solution. I have seen more problems with people sticking
entries in hosts / lmhosts including server admin types :-)

If the router gets the setting from the ISP, you should be able to
confirm those from the ISP online help / config with the router setup on
screen.

What I normally suggest at this point is,

Reset router to factory default.

Configure router for ISP settings.

Set each PC to DHCP obtain IP/DNS automaticlly (remove lmhosts file,
untick use lmhosts, make sure hosts file is the localhost entry only)

This way if it's all DHCP from the ISP to the router , DHCP from router
to PCs there isn't any manual config / local lmhosts file editing.

Look at the output of ipconfig/all , If the router is acting as a DNS
it's most likely the DNS server entry and as you say gateway 192.168.1.1
will both be the same.

Then setup a PC on the LAN for DHCP only, with no lmhosts file , and a
hosts file with only the default localhost line. Basically a default
setup from CD.

Say you run a webserver on your LAN and you want the outside world to
access it. If your ISP connection is DHCP then over the course of time
the public IP address of the router changes. DDNS is a service which
updates a DNS with the varying router address.

One such external DNS is www.dyndns.org , so you create an account with
them, confure the DDNS on the router to update the external DNS record.

This means the outside world connects to your server for example as -

greenfishcakes.com , and even though the IP address of the router
changes the DDNS config on the router associates the changing IP with
the fixed greenfishcakes.com


Don't go there.

Why not my expensive at the time , now very old and outdated netgear
router had RIP, DNS , DDNS.

Not of any use, there isn't 1 from a non ill PC to compare, and you
masked the IP address and onwards.

No paste of lmhosts? Although if it's only local PCs , it shouldn't
matter. There are no typos in any of the lmhosts files. You did edit the
file on 1 PC and copy it to the others so it's the same on each PC.



Doesn't matter blocking the MAC, it's a local setting and of no use to
anyone else.

So the rest of the lines are static entries, and your repeated use of
ipconfig / renew / release won't work.



Me

Yes, the Cable internet ISP lease. They use a VPN dial up connection,
every time I connect they give me a new IP and it has a time limited
lease.

The ISP settings in the router are okay, confirmed.
The Ipconfig /all shows that DNS servers x and y are configured as real

ISP servers, not the router address. The router address appears only in

the gateway. The router itself also has x and y defined as DNS servers.

If I change the PC's DNS server to the router address, things work but
much more slowly and many more sites don't load at all. So basically I
configured all the PC's to skip the router for DNS requests and go
straight to the internet DNS servers of the ISP, which seems to work
better for some reason.

I have tried to set DHCP only with "Automatic" settings only in the PC
(no IP or DNS servers defined manually) and it seems to work fine now
(for all sites), but I remember that this was my initial setup for all
PC's on this network (right after I added the router) and after a few
days I began having delays in DNS requests (even some pages like google
took 2-3 reloads of the page or clicks on the link to load) , which
setting up the PC's statically seemes to have improved- (pausing for
breath...)
except for the 1-2 odd sites like mail.lycos.com which still don't
load.

By the way the other reason I added the lmhosts "dodo" is that I was
advised it improves internal LAN file browsing in peer to peer networks
-helping the machines with the "Browse master" wars and so on.. even
though I have only one PC configured as Domain Master and all the
others disabled. (Incidentally the browsemaster machine is the one
having problems with accessing mail.lycos.com..)

Which reminds me, do you know how to script the mapped drives to
conditionally connect upon boot in the morning (i.e., if the remote
machine on the mapped drive is turned off, there's no error and the
authentication is delayed until later when the user actually tries to
access the mapped drive? - which by then the remote machine is likely
to have been turned on).

Thanks again for your help

On 29 Jan 2006 11:30:36 -0800, developmental2@walla.com wrote:

<big snip>

The ipconfig/all settings on a PC are the same without VPN client
running on the PC as after?
Altough not always the case, for example in the setup at work,
ipconfig/all prior to running VPN is local LAN settings, after VPN is
run the domain name / DNS servers change to those of where the VPN
server points to. When the VPN client is exited the settings return to
the LAN values.


How is that a DNS issue, a name lookup is only 2 or 3 packets. Once
that's done (although many pages link every which way to all sorts of
tracking / external ads) it's loading page times , getting all the daft
bits , graphics , multimedia etc.

If you are not sure , then try nslookup from a command line , see if
that's slow , try site names you haven't just browsed to.

OTOH clear your browser cache, do the ipconfig/flushdns then browse a
page after doing a nslookup to a site you want to browse to. The view
the site in a browser, not a great subjective test.

Look into traceroute then.

The other thing if you know the IP of a public DNS server other than
your ISP, check www.google.com

You do nslookup as before , it connects to the default server as you
expect the ISP. Instead of typing the hostname / IP at the > prompt do
this instead , without the <>

server <public DNS server IP>

If that return an answer faster or slower , maybe have a word with your
ISP, check your ISP support newsgroups.

As another example, my ISP on broadband has regional DNSs , but for
dialup there is a different pri/sec. On some ocassions broadband users
have to point to the ISP other DNS.

I figured that, although for that size of setup you mentioned it's more
of a hassle.

lmhosts really is dead, it is a hang over from Lan Manager 1.x/2.x days.

On larger networks like the type I mentioned at work , about the only
thing it's handy for is the #PRE command to include the domain
controller addresses, when you have many 100's of users trying to login
at the name time , the PC not having to resolve the DC address via DNS
or WINS does reduce traffic somewhat.

That's not too much an issue either, the name list maintainers (PCs) run
like this in ascending order NT/2000/XP/Windows Server 2003. So you
simply always leave on the system with the newest OS, as a DC.

The MaintainServerList is handled much more simply by turning it off
with a registry edit. Which someone in our place for to do on nearly all
PCs, but again it's a big issue with large quantity of PCs, when
debugging name lookup issues, disable the serverlist on 1 PC and it
jumps to another (fairly) random PC.

IIRC you said you had a workgroup, but it's been a long thread.

That's an extra complication, depending what services may be running.

He He......

We don't really have this issue as all our stuff is central file
servers, however -

We used a file on the root of common paths like global apps, the file is
only a few bytes, but only has to exist on the drive.

flag.con

The login script simply tests , does the file exist and uses an error
level. Our stuff is a mix of the built in OS stuff and Kix scripts.

You should be able to get the exact syntax (It's been 5 years at least
since I wrote login scripts) from any of the batch file tutorial sites.
There are dozens , look for some with www.google.com

Here is a starter
http://www.robvanderwoude.com/if.html

YW.

It's almost like being at work on a Sunday :-)

Me

wrote:

Thank you for your detailed reply.

why? wrote:


I've told you before, I don't care about names -- please continue.

wrote:


Do computers worry you?

wrote:


Don't you think computers can help people?

why? wrote:


I've told you before, I don't care about names -- please continue.