topic Re: using ips and ports in Operating System - HP-UX

using ips and ports

Shivkumar — Mon, 19 Jun 2006 17:39:01 GMT

Hi,

We ran out of IPs in our datacenter. Is it possible to re-use some existing IPs for different applications by
changing the ports ?

Thanks,
Shiv

Re: using ips and ports

A. Clay Stephenson — Mon, 19 Jun 2006 18:11:45 GMT

If by IP's you mean IP addresses then it is possible for a given IP address to host many tcp/ucp ports (services); however, if you mean can two devices share a common IP address then the answer is no unless they are on completely isolated networks. It would help if you clarified your problem. Are you out of IP addresses? (ie all those in your subnet are now used?) or are you out of physical connections?

Re: using ips and ports

Shivkumar — Mon, 19 Jun 2006 18:49:18 GMT

We are out of IP addresses. Wanted to host new WebLogic Server applications. For this purpose we needed more IP addresses.

best regards,
Shiv

Re: using ips and ports

A. Clay Stephenson — Mon, 19 Jun 2006 19:27:20 GMT

Then get yourself a wider subnet or use a different port number fot each server on the same IP address.

Re: using ips and ports

Steven E. Protter — Mon, 19 Jun 2006 19:47:38 GMT

Shalom Shiv,

You should never run out of IP addresses in a local network. The amount of addreses possible is nearly unlimited.

A standard network, say 192.168.0 network has a possibility of 253 usable addresses with a subnet of 255.255.255.0

If that subnet were changed to 255.255.254.0 ,creating a larger subdomain the number of possible addresses would multiply.

Lets say you like simple subnet masks, you can use a router or a converted throwaway PC to create a route between two networks.

One segment is 192.168.0 for the network portion with 253 possible addresses, the next 192.168.5 or even 10.0.0.

Your networking folks should have anticipated this long ago, unless you are the networking folk, in which case I apologize profusely.

The answer to your original question is no, one ip address at one physical location.

SEP

Re: using ips and ports

Shivkumar — Mon, 19 Jun 2006 23:00:52 GMT

If an IP starts with 15.x.x.x then how many IP addresses would be possible using various technologies such as VLAN ? I have heard of VLAN but are there any other options ? We are a very large organization and i am not a network guy but has little bit networking knowledge ( not as good as gurus of this forum :-)) )

Regards,
Shiv

Re: using ips and ports

Arunvijai_4 — Mon, 19 Jun 2006 23:04:58 GMT

Hi Shiv,

A good article to read, IP Address management

http://www.byte.com/art/9602/sec16/art4.htm

-Arun

Re: using ips and ports

Chauhan Amit — Tue, 20 Jun 2006 02:13:56 GMT

Reply is inline:

If an IP starts with 15.x.x.x then how many IP addresses would be possible using various technologies such as VLAN ?

A) If a IP starts with 15.x.x.x , First octet i.e 15 suggests that it is a class A Network

Sunet Mask for Class A network is 255.0.0.0

No. of Hosts/IP address available for this network is
256*256*256-2

-Amit

Re: using ips and ports

Chauhan Amit — Tue, 20 Jun 2006 02:16:04 GMT

Check out this link for understanding IP address and Subnetting

http://www.ralphb.net/IPSubnet/

-Amit

Re: using ips and ports

Chauhan Amit — Tue, 20 Jun 2006 02:18:57 GMT

Excellent Link for calculating the resulting broadcast, network, and host range by giving IP address and netmask .

http://jodies.de/ipcalc

Just Checked for your network , Gives

Hosts/Net: 16777214

-AMit

Re: using ips and ports

rick jones — Tue, 20 Jun 2006 19:13:54 GMT

If your IPs start with 15. you should be asking in an HP-internal forum... that, or you are using IPs in a range assigned to HP and might want to reconsider that.

In theory, one can run multiple services on the same IP on different ports, but the clients of those services tend to need to know about it - it is rarely transparant to the applications.

Re: using ips and ports

Shivkumar — Tue, 20 Jun 2006 19:24:16 GMT

Thanks Rick!! Regards. Shiv

Re: using ips and ports

rick jones — Tue, 20 Jun 2006 19:26:01 GMT

BTW VLANS has nothing to do with the number of available IP's in a net/subnet. VLANS are strictly a layer-two thing.

Re: using ips and ports

Shivkumar — Tue, 20 Jun 2006 19:29:02 GMT

Thanks everyone for their suggestions. Regards. Shiv