cancel
Showing results for 
Search instead for 
Did you mean: 
cancel
806
Views
5
Helpful
6
Replies

Company acquired Subnet issues

prakashcsco
Level 1
Level 1

HI   if   A company with 10.0.0.0/8 subnet acquired a company B which also having 10.0.0.0/8 range IP. how we can we resolve this scenario as both are using same subnet.

 

 

2 Accepted Solutions

Accepted Solutions

Jon Marshall
Hall of Fame
Hall of Fame

 

That is a large range so there may not be any overlapping but if there is basically you need to look to readdress the subnets that do. 

 

As a temporary measure you may be able to use NAT to communicate between subnets using the same range but that would only be a short term solution, you really need to readdress. 

 

Jon

View solution in original post

Jon already mentioned the best option (readdress the network) and the worst option (NAT). There is a third that at least should be evaluated: Adding IPv6 on top of both networks for the systems that need to communicate with each other.

View solution in original post

6 Replies 6

prakashcsco
Level 1
Level 1

Additing some details 

 

Company have DMVPN  and using EIGRP for routing. 

prakashcsco
Level 1
Level 1

Adding some details 

 

Company A have DMVPN  and using EIGRP for routing. 

Jon Marshall
Hall of Fame
Hall of Fame

 

That is a large range so there may not be any overlapping but if there is basically you need to look to readdress the subnets that do. 

 

As a temporary measure you may be able to use NAT to communicate between subnets using the same range but that would only be a short term solution, you really need to readdress. 

 

Jon

Jon already mentioned the best option (readdress the network) and the worst option (NAT). There is a third that at least should be evaluated: Adding IPv6 on top of both networks for the systems that need to communicate with each other.

Joseph W. Doherty
Hall of Fame
Hall of Fame

Just to add to what @Jon Marshall and @Karsten Iwen have noted, the NAT they refer to, I believe, is known as "double NAT".

Another issue you can easily run into, especially in the case of using two /8s, what address block do you map to for the other side to "see"?

Having been in this situation, i.e. merging two companies both using 10.0.0.0/8, you may end up NATting only some address blocks that really, really need to be accessed from the other side.  You then work, to try to partition 10.0.0.0/8 such that it can be "shared", without overlap, by the two companies.

BTW, in the (rather large) company where I encountered this situation, the new to be added company only used part of 10.0.0.0/8, as most companies would, however, our company actually used all of 10.0.0.0/8 (and 172.16.0.0/12 and 192.168.0.0/16).  (We were early adopters of IPv6 due to depletion of all IPv4 private address space.)

Leo Laohoo
Hall of Fame
Hall of Fame

@prakashcsco wrote:

A company with 10.0.0.0/8 subnet acquired a company B which also having 10.0.0.0/8 range IP.


That's a trick question.  10.0.0.0/8 is a private IP address.  No single individual or company "owns" this subnet.  

Getting Started

Find answers to your questions by entering keywords or phrases in the Search bar above. New here? Use these resources to familiarize yourself with the community: