1 IP / Configuration Address for many addresses


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Does anyone know the name of what it is called when you have 1 Configuration Address and behind that there is a dynamic listing of IPs.

I can't remember the name I know I have seen Google use this in some cases and I believe it starts with letter a "v" or "s".

Describing the example in theory:

Config Main Address - v sf 192.168.0.1

This would be linked to the following addresses:

192.168.0.2

192.168.0.3

192.168.0.4

192.168.1.2

192.168.2.3

I would only have to remember or use the "Config Main Address" and not worry about all the others.

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huh?? what is the mask on that address if your able to link to 192.168.1, .2 and 192.168.3 addresses? And you say these are dynamic?

On what would you do this? a PC, router?

Do you mean creating multiple IPs on the same interface, say a VIP (virtual IP) those are not dynamic in nature. Or do you mean NAT from one address to a different address or NAPT? where you map ports on 1 ip address to ports on different address which is what most soho routers default to do.

What are you trying to accomplish?

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VLSM? Hmmm possible that is what he is after, but I agree with you if that is what he is looking for - he is no where close to the right description ;) Better guess than I had -- I read the post multiple times and just clueless to what he is looking for.

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After re-reading what I wrote and seeing what you all were guessing at. It wasn't what I was looking for. I see why you were guessing what you were thinking of, I am not the best explainer for what I am after.

Thanks for sticking with me and trying.

I was off by a lot....I found it...

Create a TXT record containing this text:

Does this record work for IP addresses too or is this only good for MX records?

v=spf1 include:_spf.google.com ~all

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After re-reading what I wrote and seeing what you all were guessing at. It wasn't what I was looking for. I see why you were guessing what you were thinking of, I am not the best explainer for what I am after.

Thanks for sticking with me and trying.

I was off by a lot....I found it...

Create a TXT record containing this text:

Does this record work for IP addresses too or is this only good for MX records?

v=spf1 include:_spf.google.com ~all

I think SPF is only really affect MX records.

You can use an IP address in the SPF record. If you have a block of IPs, you can set them up with 100.2.3.12/24 for example.

Otherwise you might be better off using a domain. This would give pretty you what you were asking of in the first post.

An A record with domain.com with a pool of IPs

Then your SPF record linked to domain.com.

Any changes made to A record domain.com will then change your SPF. The affect is controlling all IPs in the DNS pool.

I'm sure Budman can explain it better if that's what you're actually after.

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I actually thought he meant NAT but now I am not so sure.

1 Configuration Address and behind that there is a dynamic listing of IPs

One Main Address i.e Public Facing, Then Dynamic ones BEHIND IT...NAT'ING? Network Address Translation?

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Ok this is why I am going to ask this again vs you explaining what your after

"What are you trying to accomplish?"

You want to create a spf record? That is for verification of email sender, has nothing to do with dynamic addresses to be honest.. Now if you use say A and -all then sure any A record would match and be ok

ALL Matches always; used for a default result like -all for all IPs not matched by priorm echanisms.

A If the domain name has an address record (A or AAAA) that can be resolved to the sender's address, it will match.

IP4 If the sender is in a given IPv4 address range, match.

IP6 If the sender is in a given IPv6 address range, match.

MX If the domain name has an MX record resolving to the sender's address, it will match (i.e. the mail comes from one of the domain's incoming mail servers).

PTR If the domain name (PTR record) for the client's address is in the given domain and that domain name resolves to the client's address (forward-confirmed reverse DNS), match.

EXISTS If the given domain name resolves to any address, match (no matter the address it resolves to). This is rarely used. Along with the SPF macro language it offers more complex matches like DNSBL-queries.

INCLUDE If the included (a misnomer) policy passes the test this mechanism matches. This is typically used to include policies of more than one ISP.

you can qualify those with + - ~ ?

etc.. etc..

So again I ask

"What are you trying to accomplish?"

And what DNS are you using?? If you tryng to create spf record.

You may list different things for your spf record, but is only a TXT record.. Its not dynamic in any way, and its only used for verification of a some server sending email.. So if your trying to use it for some other purpose?

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Does anyone know the name of what it is called when you have 1 Configuration Address and behind that there is a dynamic listing of IPs.

I think you are confusing terms

subnet describes the range of addresses

dhcp describes allocating them dynamically

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I agree with budman. Explain what you are trying to do vs explaining it and you will get better help. From your description it almost sounds like nat with multiple VLANs.

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So what are you trying to do?? Why do/did you think that spf record was something your after if that is what your asking about?

Where did you come up with

"Config Main Address - v sf 192.168.0.1"

If you explain to us what your wanting to happen - then there are plenty of people here that can most likely give you 20 different ways to skin the specific cat your chasing.

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