?
Solved

Understanding IP Ranges

Posted on 2011-09-14
8
Medium Priority
?
471 Views
Last Modified: 2012-05-12
Our company IP addressing is as follows:

10.213.0.0/19 or 255.255.224.0 (1st Network)
10.213.253.0/29 or 255.255.255.248 (Router network to Sister Company)
10.213.253.8/29 or 255.255.255.248 (Router to ISP)

On our MPLS Router (Inside IP 10.213.253.2/29) I have been asked to supply an IP address for loopback on the range 10.213.0.x/32 or any /32 host IP.

What range of IP would match this?
0
Comment
Question by:DHPBilcare
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 4
  • 2
  • 2
8 Comments
 
LVL 18

Accepted Solution

by:
Garry Glendown earned 1000 total points
ID: 36538647
Just pick any IP that is not part of an otherwise used IP subnet. Effectively, it's just an additional IP for your router, usable for things like PPP originator, VPN, Tunnels, etc ...
0
 
LVL 25

Assisted Solution

by:Ken Boone
Ken Boone earned 1000 total points
ID: 36538664
Well we really need to understand the whole ip scheme of things.

So you have a 10.213.0.0 /19 network which can mean a few things.

It might mean that you company supplied you with this block of IPs for you to use internally however you see fit.

So right now that block is 10.213.0.0 - 10.213.31.255

So that is the equivalent of 8190 hosts on the network.  Which is either crazy to put on one network or sheer laziness or lack of understanding.

So most likely what was intended is for your part of the company that has that block to further subdivide or subnet that block into usable ranges that you can disperse however you want.

In other words you might use 10.213.0.0 / 24 and 10.213.1.0 / 24 and 10.213.2.0 / 24 for different vlans in your internal network, but the rest of your company just sees the 10.213.0.0/19.

So if that is how it is being used you need to find out how your ip block has been allocated and then determine what you have left to use.

So lets look at the 3rd octet.  It can range from 0 - 31 and still be in your assigned block.  Lets say you have used 0 - 10 already as /24 networks.  So we can't reuse them.  So maybe we reserve the .31 portion of the address specific to loopbacks.  So we won't use those as a /24 instead we will use them as /32 addresses.

It really depends on how your IP scheme is actually laid out.  For instance on your 1st network - do the PCs on that network really have a subnet mask of /19?

0
 

Author Comment

by:DHPBilcare
ID: 36538739
At the moment the network is flat but the potential to grow and add VLANS in the future as required.  

We have been allocated the range listed for our own use.
0
Plug and play, no additional software required!

The ATEN UE3310 USB3.1 Gen1 Extender Cable allows users to extend the distance between the computer and USB devices up to 10 m (33 ft). The UE3310 is a high-quality, cost-effective solution for professional environments such as hospitals, factories and business facilities.

 
LVL 25

Expert Comment

by:Ken Boone
ID: 36538770
so if its a flat /19 network then you will not be able to give the router anything in the 10.230.[0-31].x range as it will overlap.

You will have to go outside of that block in order to do that.

Is the deal such that each company under the conglomerate got a separate block of addresses to use?  If so you will have to see what is free.  Since you guys are flat with a /19 nothing is available for you to use out of that block.  The router will not let you configure an overlapping ip address on the same router.
0
 
LVL 18

Expert Comment

by:Garry Glendown
ID: 36538797
Can you say what the Loopback IP will be used for?
Anyway, I would suspect you could maybe use a /32 from the 10.213.253.0/24 network, e.g. 10.213.253.255/32 ...
0
 

Author Comment

by:DHPBilcare
ID: 36538843
Sorry my mistake.

The MPLS router is outside of our firewall on a subnet of 10.213.253.0/29.

As this router requires the IP for loop back could I not simply exclude .31 portion from the internal pool and use one address on said router?  e.g. 10.213.31.1 /32.
0
 
LVL 25

Expert Comment

by:Ken Boone
ID: 36539219
No because your router has an inside interface on the 10.213.0.0 / 19 interface.  If you created another interface on the router using 10.213.31.1 the router will bark at you and tell you that you are trying to use an overlapping interface.  You have to go outside the 0-31 range.

You can re-subnet your network so you don't have this problem in the future.  You said you want to grow, but you can't grow in this address space unless you re-address your network and use it more efficiently.
0
 
LVL 25

Expert Comment

by:Ken Boone
ID: 36539223
This really has nothing to do with the pool of addresses it has all to do with the fact that it overlaps.
0

Featured Post

Free Tool: SSL Checker

Scans your site and returns information about your SSL implementation and certificate. Helpful for debugging and validating your SSL configuration.

One of a set of tools we are providing to everyone as a way of saying thank you for being a part of the community.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

In the hope of saving someone else's sanity... About a year ago we bought a Cisco 1921 router with two ADSL/VDSL EHWIC cards to load balance local network traffic over the two broadband lines we have, but we couldn't get the routing to work consi…
Tired of waiting for your show or movie to load?  Are buffering issues a constant problem with your internet connection?  Check this article out to see if these simple adjustments are the solution for you.
After creating this article (http://www.experts-exchange.com/articles/23699/Setup-Mikrotik-routers-with-OSPF.html), I decided to make a video (no audio) to show you how to configure the routers and run some trace routes and pings between the 7 sites…
After creating this article (http://www.experts-exchange.com/articles/23699/Setup-Mikrotik-routers-with-OSPF.html), I decided to make a video (no audio) to show you how to configure the routers and run some trace routes and pings between the 7 sites…
Suggested Courses

801 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question