windows server Changing default IP address when running server on two subnets?

[Guest Fox1977]

Hi there,

 

I have a windows 2003 server with two network cards in running on two

seperate subnets. These are running behind a firewall that (at

present) doesnt route between the subnets.

 

I have had to add the second card to the server in order to add the

additional subnet as we needed to use more IP addresses. This server

is in a data centre running a number of websites for our company.

 

The server is running with the two subnets and by default all of the

outgoing requests are going out on the new subnet. This is a bit of

an issue as the server is part of a bigger network and there are a lot

of routing rules in place. How do i get the requests to come from the

server with the source IP address as the first subnet that was running

on there?

 

I have gone into the network connections > advanced > advanced

settings and changed the order of the network cards so it uses the

first network card/subnet but it still hasnt applied the changes. Why

i go to an IP lookup website it still lists the new subnet as the

source.

 

Any ideas? Does the server need a reboot for the changes to apply?

[Guest Phillip Windell]

1. It follows the Nic with the Default Gateway.

 

2. It doesn't matter how many subnets there are,...the server should have

only one Nic and "live" on only one subnet.

 

--

Phillip Windell

 

The views expressed, are my own and not those of my employer, or Microsoft,

or anyone else associated with me, including my cats.

-----------------------------------------------------

 

 

"Fox1977" wrote in message

news:f4c462a6-bb2b-4def-bba6-e7cbb27c7aa9@f16g2000vbf.googlegroups.com...

> Hi there,

>

> I have a windows 2003 server with two network cards in running on two

> seperate subnets. These are running behind a firewall that (at

> present) doesnt route between the subnets.

>

> I have had to add the second card to the server in order to add the

> additional subnet as we needed to use more IP addresses. This server

> is in a data centre running a number of websites for our company.

>

> The server is running with the two subnets and by default all of the

> outgoing requests are going out on the new subnet. This is a bit of

> an issue as the server is part of a bigger network and there are a lot

> of routing rules in place. How do i get the requests to come from the

> server with the source IP address as the first subnet that was running

> on there?

>

> I have gone into the network connections > advanced > advanced

> settings and changed the order of the network cards so it uses the

> first network card/subnet but it still hasnt applied the changes. Why

> i go to an IP lookup website it still lists the new subnet as the

> source.

>

> Any ideas? Does the server need a reboot for the changes to apply?

[Guest foxj77]

Hi Phillip,

 

Unfortunately the server has default gateways on both NICs!

 

On 14 July, 14:36, "Phillip Windell" wrote:

> 1. It follows the Nic with the Default Gateway.

>

> 2. It doesn't matter how many subnets there are,...the server should have

> only one Nic and "live" on only one subnet.

>

> --

> Phillip Windell

>

> The views expressed, are my own and not those of my employer, or Microsoft,

> or anyone else associated with me, including my cats.

> -----------------------------------------------------

>

> "Fox1977" wrote in message

>

> news:f4c462a6-bb2b-4def-bba6-e7cbb27c7aa9@f16g2000vbf.googlegroups.com...

>

> > Hi there,

>

> > I have a windows 2003 server with two network cards in running on two

> > seperate subnets.  These are running behind a firewall that (at

> > present) doesnt route between the subnets.

>

> > I have had to add the second card to the server in order to add the

> > additional subnet as we needed to use more IP addresses.  This server

> > is in a data centre running a number of websites for our company.

>

> > The server is running with the two subnets and by default all of the

> > outgoing requests are going out on the new subnet.  This is a bit of

> > an issue as the server is part of a bigger network and there are a lot

> > of routing rules in place.  How do i get the requests to come from the

> > server with the source IP address as the first subnet that was running

> > on there?

>

> > I have gone into the network connections > advanced > advanced

> > settings and changed the order of the network cards so it uses the

> > first network card/subnet but it still hasnt applied the changes.  Why

> > i go to an IP lookup website it still lists the new subnet as the

> > source.

>

> > Any ideas?  Does the server need a reboot for the changes to apply?

>

>

[Guest Ace Fekay [MCT]]

"foxj77" wrote in message

news:1d5753a7-4861-43a4-8ae9-d04030c38bf8@m18g2000vbi.googlegroups.com...

>

> Hi Phillip,

>

> Unfortunately the server has default gateways on both NICs!

 

Hello Fox,

 

Unfortunately, that is not a good practice. A default gateway is the gateway

to the 'world,' so to speak. It's kind of saying to someone, there are two

doorways out of this room to get to the outside of the building. The person

is able to decide which one is better to use, however, when it comes to a

computer, that is not possible. The idea is to have only one default gateway

on any machine and allow the network infrstructure (routers) decide the best

way out the door.

 

Also, if this is a DC, or it has DNS installed on it, and worse, the

combination of either of the two and RRAS installed, makes it much more

difficult. If this is a DC, or you want to control which NIC gets registered

into DNS (all will get registered if the previous one of three roles are on

this machine), I have a complete blog on how to set it up.

 

Otherwise, I agree with Phillip in that one gateway and one NIC and allow

the machine to do it's job and your network to do the rest.

 

--

Ace

 

This posting is provided "AS-IS" with no warranties or guarantees and

confers no rights.

 

Please reply back to the newsgroup or forum to benefit from collaboration

among responding engineers, and to help others benefit from your resolution.

 

Ace Fekay, MCT, MCSE, MCSA 2003 & 2000, MCSA Messaging

Microsoft Certified Trainer

aceman@mvps.RemoveThisPart.org

http://twitter.com/acefekay

 

For urgent issues, you may want to contact Microsoft PSS directly. Please

check http://support.microsoft.com for regional support phone numbers.

[Guest Phillip Windell]

"foxj77" wrote in message

news:1d5753a7-4861-43a4-8ae9-d04030c38bf8@m18g2000vbi.googlegroups.com...

> Hi Phillip,

> Unfortunately the server has default gateways on both NICs!

 

You'll have to stop doing that. "Default",...by definition,...means there

can only be one. Windows will even warn of this when you try to apply a

Gateway to a Nic when another Nic in the machine already has one.

 

There is a such thing as Dead Gateway Detection,...but it does not in any

way apply to this situation.

 

You also need to get rid of the other Nics. Use a Router to join the

subnets,..use the same Router for ACLs to restrict/allow traffic between the

subnets according to company policy. The Server needs to have one

nic,...and have a single "identitiy",....on a single subnet.

 

 

--

Phillip Windell

 

The views expressed, are my own and not those of my employer, or Microsoft,

or anyone else associated with me, including my cats.

-----------------------------------------------------

[Guest foxj77]

I've tried setting the new nic with the second subnet with no gateway

but the IP addresses dont work. I can only ping IP addresses on the

new subnet when the gateway is in the second nic.

 

The thing i am struggling to understand is why the options are there

in the advanced settings in the network connections but they dont seem

to make any difference.

 

I appreciate this is not the best way to do things but it is only a

temporary fix for a couple of months.

 

Thanks for the assitance

 

On 14 July, 16:01, "Ace Fekay [MCT]"

wrote:

> "foxj77" wrote in message

>

> news:1d5753a7-4861-43a4-8ae9-d04030c38bf8@m18g2000vbi.googlegroups.com...

>

>

>

> > Hi Phillip,

>

> > Unfortunately the server has default gateways on both NICs!

>

> Hello Fox,

>

> Unfortunately, that is not a good practice. A default gateway is the gateway

> to the 'world,' so to speak. It's kind of saying to someone, there are two

> doorways out of this room to get to the outside of the building. The person

> is able to decide which one is better to use, however, when it comes to a

> computer, that is not possible. The idea is to have only one default gateway

> on any machine and allow the network infrstructure (routers) decide the best

> way out the door.

>

> Also, if this is a DC, or it has DNS installed on it, and worse, the

> combination of either of the two and RRAS installed, makes it much more

> difficult. If this is a DC, or you want to control which NIC gets registered

> into DNS (all will get registered if the previous one of three roles are on

> this machine), I have a complete blog on how to set it up.

>

> Otherwise, I agree with Phillip in that one gateway and one NIC and allow

> the machine to do it's job and your network to do the rest.

>

> --

> Ace

>

> This posting is provided "AS-IS" with no warranties or guarantees and

> confers no rights.

>

> Please reply back to the newsgroup or forum to benefit from collaboration

> among responding engineers, and to help others benefit from your resolution.

>

> Ace Fekay, MCT, MCSE, MCSA 2003 & 2000, MCSA Messaging

> Microsoft Certified Trainer

> ace...@mvps.RemoveThisPart.orghttp://twitter.com/acefekay

>

> For urgent issues, you may want to contact Microsoft PSS directly. Please

> checkhttp://support.microsoft.comfor regional support phone numbers.

[Guest Phillip Windell]

"foxj77" wrote in message

news:1096baba-0981-4afc-954c-fdddc8147b94@f33g2000vbm.googlegroups.com...

> I've tried setting the new nic with the second subnet with no gateway

> but the IP addresses dont work. I can only ping IP addresses on the

> new subnet when the gateway is in the second nic.

 

It is because it is a Server,...not a LAN Router.

You are not supposed to be able to ping it by any other IP on any other Nic.

You can only ping from a Host that is on the same subnet as the IP you

pinged, and even that assumes that the source and destination on on the same

"wire",...then same physical layer.

You need to stop createing problems you shouldn't create then try to solve

the problems that shouldn't have been created.

 

Run the Server on one IP#,...on one Nic,...on one subnet.

 

--

Phillip Windell

 

The views expressed, are my own and not those of my employer, or Microsoft,

or anyone else associated with me, including my cats.

-----------------------------------------------------

[Guest Ace Fekay [MCT]]

"foxj77" wrote in message

news:1096baba-0981-4afc-954c-fdddc8147b94@f33g2000vbm.googlegroups.com...

> I've tried setting the new nic with the second subnet with no gateway

> but the IP addresses dont work. I can only ping IP addresses on the

> new subnet when the gateway is in the second nic.

>

> The thing i am struggling to understand is why the options are there

> in the advanced settings in the network connections but they dont seem

> to make any difference.

>

> I appreciate this is not the best way to do things but it is only a

> temporary fix for a couple of months.

>

> Thanks for the assitance

 

You can't ping the other IP address because there is no route to it in your

infrastructure. This is a routing issue with your network.

 

Do you have a Visio of your network and what you're trying to do? Use this

Visio as an example of how to construct an Visio that is easy to read and

understand. This should also give you an idea what we're talking about

concerning routing within a network.

http://www.fekay.com/supportblogs/staticrouteexample.htm

 

Also, what options are you referring to? To create multiple gateways? I have

four German Shepherds, two of which are police trained protection dogs. They

are extremely intelligent and smart, and if I try to get them to do

something that's not possible, they just look at me as if saying, What - you

know that ain't possible, right?? And they won't do it. The operating system

is very intelligent, but it ain't that smart, so there may not be any

built-in warning, so it relies on us to know its limitations.

 

Ace

[Guest Kevin Longley]

What functions is the server providing on the network?

 

"Fox1977" wrote in message

news:f4c462a6-bb2b-4def-bba6-e7cbb27c7aa9@f16g2000vbf.googlegroups.com...

> Hi there,

>

> I have a windows 2003 server with two network cards in running on two

> seperate subnets. These are running behind a firewall that (at

> present) doesnt route between the subnets.

>

> I have had to add the second card to the server in order to add the

> additional subnet as we needed to use more IP addresses. This server

> is in a data centre running a number of websites for our company.

>

> The server is running with the two subnets and by default all of the

> outgoing requests are going out on the new subnet. This is a bit of

> an issue as the server is part of a bigger network and there are a lot

> of routing rules in place. How do i get the requests to come from the

> server with the source IP address as the first subnet that was running

> on there?

>

> I have gone into the network connections > advanced > advanced

> settings and changed the order of the network cards so it uses the

> first network card/subnet but it still hasnt applied the changes. Why

> i go to an IP lookup website it still lists the new subnet as the

> source.

>

> Any ideas? Does the server need a reboot for the changes to apply?

[Guest foxj77]

The server is a web/database server. We have to run the server with

two nics as we have the two subnets on two different vlans on our

network. There is a routing issue where the firewall cannot route

between the two subnets as they are running on subinterfaces. We are

working to get the firewall swapped for another model i know this is a

pretty obvious flaw!

 

The sites that are running on the two subnets do not need to talk to

the other subnet and this is why we have tried to implement it this

way.

 

I have rebooted the box and managed to get it change the default IP

address ok.

 

The only issue I have now is that we are getting intermittent short

5-10 second outages on each alternative subnet. There's no pattern

with the outages. Anyone any ideas why.

 

Thanks for the advice so far.

 

Thanks

 

 

On 15 July, 00:43, "Kevin Longley" wrote:

> What functions is the server providing on the network?

>

> "Fox1977" wrote in message

>

> news:f4c462a6-bb2b-4def-bba6-e7cbb27c7aa9@f16g2000vbf.googlegroups.com...

>

> > Hi there,

>

> > I have a windows 2003 server with two network cards in running on two

> > seperate subnets.  These are running behind a firewall that (at

> > present) doesnt route between the subnets.

>

> > I have had to add the second card to the server in order to add the

> > additional subnet as we needed to use more IP addresses.  This server

> > is in a data centre running a number of websites for our company.

>

> > The server is running with the two subnets and by default all of the

> > outgoing requests are going out on the new subnet.  This is a bit of

> > an issue as the server is part of a bigger network and there are a lot

> > of routing rules in place.  How do i get the requests to come from the

> > server with the source IP address as the first subnet that was running

> > on there?

>

> > I have gone into the network connections > advanced > advanced

> > settings and changed the order of the network cards so it uses the

> > first network card/subnet but it still hasnt applied the changes.  Why

> > i go to an IP lookup website it still lists the new subnet as the

> > source.

>

> > Any ideas?  Does the server need a reboot for the changes to apply?

>

>