When we increased our block of 8 static IP addresses to 16, the base IP
changed which caused us a bit of a problem because we weren't told when it
was going to happen - all of a sudden our external comms went down and we
had to reconfigure firewall, servers, A records etc.

Now we require an additional 5 static IP's, our ISP is saying we can't have
another block of 8 numbers, we have to go to a block of 32 contiguous
numbers - which means our current static IP addresses will be lost again!
Our 'static' IPs are changing more often than our dynamic ones ever did!

My question - is there a technical reason why we can't have two blocks of
static IP addresses?
Our ADSL router is a Zyxel Prestige 600

TIA

Pete

In article ,
(Chris) wrote:


Just out of interest, what do you need all those IP's for anyway?

Probably the same thing I need a /24 for.

--
Paul Cummins - Always a NetHead
Wasting bandwidth since 1981

begin Once upon a time there was a badly broken newsreader...

"PM" wrote in message
...
When we increased our block of 8 static IP addresses to 16, the base IP
changed which caused us a bit of a problem because we weren't told when it
was going to happen - all of a sudden our external comms went down and we
had to reconfigure firewall, servers, A records etc.

Now we require an additional 5 static IP's, our ISP is saying we can't
have
another block of 8 numbers, we have to go to a block of 32 contiguous
numbers - which means our current static IP addresses will be lost again!
Our 'static' IPs are changing more often than our dynamic ones ever did!

My question - is there a technical reason why we can't have two blocks of
static IP addresses?
Our ADSL router is a Zyxel Prestige 600

TIA

Pete



There should be no reason why they simply can't just change your /29
allocation to a /28 if you have justification for it. Heaven only knows why
they think you need a /27 on an ADSL circuit.

Just out of interest, what do you need all those IP's for anyway?

Chris.

Can you please tell us why you need all those ip addresses. I am honestly
curious and not trying to flame you.

bart
http://www.meshcode.net

"PM" wrote in message
...
When we increased our block of 8 static IP addresses to 16, the base IP
changed which caused us a bit of a problem because we weren't told when it
was going to happen - all of a sudden our external comms went down and we
had to reconfigure firewall, servers, A records etc.

Now we require an additional 5 static IP's, our ISP is saying we can't
have
another block of 8 numbers, we have to go to a block of 32 contiguous
numbers - which means our current static IP addresses will be lost again!
Our 'static' IPs are changing more often than our dynamic ones ever did!

My question - is there a technical reason why we can't have two blocks of
static IP addresses?
Our ADSL router is a Zyxel Prestige 600

TIA

Pete

On 2003-12-10, PM wrote:
My question - is there a technical reason why we can't have two blocks of
static IP addresses?

No fundamental technical reason, but it's not normally worth the effort
involved for a small block.

At present you have 16 addresses, of which some (probably 3 - network,
broadcast and the routers IP) will be used by your network infrastructure.
If you add another block of 8 then, because they don't join on to the
existing range, you'll lose another three IPs so you'll have 24 IP addresses
of which 6 are taken up by the system - not a particularly good ratio :-)

You'd also have the problem of arranging for the two sections of your
network to talk to each other - as they'll now be on different IP ranges
some machines won't be able to see others directly. Again, this isn't a
major issue and may not even be relevant to you, but it makes things messy
and is usually best avoided where possible.

If you've recently gone from 8 to 16 addresses then your ISP may well feel
that there's no point in giving you another 8 when you'll only be back to
them shortly looking for more - you may as well go to 32 now and get it
over with for a while.

The biggest sticking point you may have is that the ISP needs to route both
blocks of IP down your ADSL line. There's nothing imposible about this in
principle, but you may find that there aren't systems in place to allow this
type of configuration to be entered into their (or BTs) systems. Many ISPs
will be allocating this IP to you and configuring your and their routers in
a standardised way - it's just not worth their while to do a custom
configuration for individual customers until you get to a certain cost
point. Smaller ISPs or business orientated (that is, more expensive) ones
may be a better bet (though that won't overcome BT limitations if there are
any but they may be more imaginative about suggesting other solutions).

I'm not sure if there's a BT limitation that prevents the running of two
address ranges over one BT supplied ADSL line, I suspect there may be but
I'm open to comments.

If you are able to persuade the ISP to route the addresses to you, then you
may find that your router won't allow two separate ranges of public IPs to
be used across it - it may be that it assumes that any additional IP ranges
are for the purposes of NAT. I'm not familiar with your router so I can't
advise whether this will be a problem for you.

Glyn

Hint of the day: If you know in advance that you will be making DNS changes
in the near future and you have full control of the DNS records then lower
the Time To Live value. That way the old values will be removed from DNS
caches more quickly than normal at the expense of more DNS traffic.
Remember to put the timeouts back to normal afterwards.

"Glyn Grinstead" wrote in message
...
On 2003-12-10, PM wrote:
My question - is there a technical reason why we can't have two blocks
of
static IP addresses?

No fundamental technical reason, but it's not normally worth the effort
involved for a small block.

At present you have 16 addresses, of which some (probably 3 - network,
broadcast and the routers IP) will be used by your network infrastructure.
If you add another block of 8 then, because they don't join on to the
existing range, you'll lose another three IPs so you'll have 24 IP
addresses
of which 6 are taken up by the system - not a particularly good ratio :-)

You'd also have the problem of arranging for the two sections of your
network to talk to each other - as they'll now be on different IP ranges
some machines won't be able to see others directly. Again, this isn't a
major issue and may not even be relevant to you, but it makes things messy
and is usually best avoided where possible.

If you've recently gone from 8 to 16 addresses then your ISP may well feel
that there's no point in giving you another 8 when you'll only be back to
them shortly looking for more - you may as well go to 32 now and get it
over with for a while.

The biggest sticking point you may have is that the ISP needs to route
both
blocks of IP down your ADSL line. There's nothing imposible about this in
principle, but you may find that there aren't systems in place to allow
this
type of configuration to be entered into their (or BTs) systems. Many ISPs
will be allocating this IP to you and configuring your and their routers
in
a standardised way - it's just not worth their while to do a custom
configuration for individual customers until you get to a certain cost
point. Smaller ISPs or business orientated (that is, more expensive) ones
may be a better bet (though that won't overcome BT limitations if there
are
any but they may be more imaginative about suggesting other solutions).

I'm not sure if there's a BT limitation that prevents the running of two
address ranges over one BT supplied ADSL line, I suspect there may be but
I'm open to comments.

If you are able to persuade the ISP to route the addresses to you, then
you
may find that your router won't allow two separate ranges of public IPs to
be used across it - it may be that it assumes that any additional IP
ranges
are for the purposes of NAT. I'm not familiar with your router so I can't
advise whether this will be a problem for you.

Glyn

Hint of the day: If you know in advance that you will be making DNS
changes
in the near future and you have full control of the DNS records then lower
the Time To Live value. That way the old values will be removed from DNS
caches more quickly than normal at the expense of more DNS traffic.
Remember to put the timeouts back to normal afterwards.


Thanks to all that replied. The reason we need more IP addresses is to have
a DMZ so we can VPN to clients' sites - NAT and VPN don't like each other.
We need 5 additional addresses, the network and broadcast would take another
two so we'd have one spare.
There's no fundamental reason why we can't have contiguous addresses, it
just makes the firewall more prone to mistakes; also we really don't want to
have to reconfigure it all, get our A records changed and so on.

Unfortunately we don't configure our router - our ISP does this. I don't
know whether this is the sticking point. Unfortunately neither Tech or Sales
at the ISP could give me an answer :-( and I picked them because their
initial tech support was so good. Praps I'll drop them a mail.

Pete

On Thu, 11 Dec 2003 09:44:02 +0000, (Peter) wrote:

Hello,

I can't get BB yet (in a village and only 75 signed up to date on
bt.com) but when I can I will set up online shopping for my business.

Doesn't running a website on an in-house server need a fixed IP?

I know that in the bast there have been IP translation services around
but it doens't look very good for a business.

Yes, it will be a lot less troublesome with a static IP.
--
Dan Ros, Nildram.

The views expressed in this message may
not be that of Nildram Ltd unless indicated.

On Thu, 11 Dec 2003, Peter wrote:

Doesn't running a website on an in-house server need a fixed IP?

I know that in the bast there have been IP translation services around
but it doens't look very good for a business.

You are right - you can run a site from a dynamic IP using one of the
dynamic DNS services. You are also right that it often looks
unprofessional.

If you want to host such a site on the end of a broadband connection a
static IP is a must.

That said if you are expecting the site to get at all busy it's generally
better to host it with a professional hosting service.

Jason Clifford
--
JustADSL 1Mb Home ADSL just £31.99 / month
http://www.justadsl.com/ Business ADSL from £30/month

On Thu, 11 Dec 2003 09:44:02 +0000, (Peter) wrote:

Hello,

I can't get BB yet (in a village and only 75 signed up to date on
bt.com) but when I can I will set up online shopping for my business.

Doesn't running a website on an in-house server need a fixed IP?

I know that in the bast there have been IP translation services around
but it doens't look very good for a business.

I have recently installed broadband and bought a more expensive ADSL
modem/router than the norm, a Vigor 2600 at just under 150ukp whereas
the popular makes can be bought for just over 100.

This modem is very user configurable and can allow any incoming
requests to be forwarded to a specific machine on your network that
runs a server. Otherwise any incoming requests that are not related to
an outgoing requests are normally dropped.

Fixed IP may be preferable but dynamic can be done.

Geoff Lane
Welwyn Hatfield Computer Club - Hertfordshire, UK
www.whcc.co.uk - Online facilities for non locals

On 11 Dec 2003, "PM" wrote:

Unfortunately we don't configure our router - our ISP does this. I don't
know whether this is the sticking point. Unfortunately neither Tech or Sales
at the ISP could give me an answer :-( and I picked them because their
initial tech support was so good. Praps I'll drop them a mail.

Given you want more, you could just as easily get a second ADSL account
from someone else - then you have a reserve as well. Don't have the ISP
handling the config and you'll probably be better off anyway. I had been
meaning to ask earlier, but now am even more curious - which ISP is it at
the moment ? Thanks. Peter M.