Posted: May 12th, 2017

 

What is IP Mapping?

 

IP mapping could be a big variety of things, but is commonly referred to as a function of NAT (network address translation).

 

Essentially in a basic home situation one would have a router with several computers connected to it internally. In theory the exterior IP (often incorrectly called the WAN address by manufacturers) would be you actual ip address, where as the internal machines typicaly would have an address in the 10.x.x.x or 192.x.x.x range.

IP mapping is often used to tell a connection to route to another IP address

 

Migration from one Server to Another/New one

 

To ensure that the domains migrated from the source server are operational on the destination, it is necessary to change their configuration so that they use the IP addresses present on the destination server. This procedure is called IP mapping, and it can be performed either automatically or manually.

 

Ideally, you should have a shared IP address on the destination server for every shared IP address on the source server. The same goes for dedicated IP addresses.

 

Once the migration is finished, you can review the IP addresses assigned by the Migrator and re-assign them, as necessary.

 

Automatic IP Mapping

 

By default, IP mapping is performed automatically during the course of a migration (no user input required). Plesk Migrator attempts to re-assign the domains being migrated to the IP addresses on the destination server according to the following rules:

 

> An unallocated dedicated IP address is assigned to domains that were assigned a dedicated IP address on the source server, if possible. Otherwise (for example, if there are no unallocated dedicated IP addresses remaining on the destination server), the default shared IP address is used instead.

 

> Plesk Migrator attempts to assign all domains that used the same shared IP address on the source server to a separate shared IP address on the destination server, if possible. Otherwise (for example, if there are fewer shared IP addresses on the destination server than on the source server), the default shared IP address is used instead.

 

IP mapping can also be performed manually, either with the help of the IP mapping file, or the migration list file.

 

 

​Note: It is possible to combine different ways of mapping. For example, you can specify common mapping rules using the migration list, and then set specific addresses for some particular domains using the mapping file.

 

IP Mapping Using the Mapping File

 

An IP mapping file is a simple plain text file containing two columns of IP addresses separated by the whitespace character. The IP addresses in the left column are those present on the source server, and they are matched to the corresponding IP addresses from the destination server in the right column. The file should contain nothing except the IP addresses (no comments and such). Blank lines are allowed.

 

Here are the contents of a sample IP mapping file:

 

192.168.1.10 10.52.1.16

192.168.1.11 10.52.1.17

192.168.1.12 10.52.1.17

 

In this example, domains using the IP address 192.168.1.10 will be assigned the IP address 10.52.1.16. Those using the IP addresses 192.168.1.11 and 192.168.1.12, will be assigned the IP address 10.52.1.17.

 

Once you have prepared the mapping file, you can pass it to the Plesk Migrator using the following option:

 

--ip-mapping-file IP_MAPPING_FILE

 

where IP_MAPPING_FILE is the path to the mapping file (either absolute or relative to the current working directory).

 

IP Mapping Using the Migration List File

 

This method of IP mapping is more complicated, but gives a greater degree of control over IP address assignment. The procedure for generating the migration list file is described in the Migrating from Plesk Servers topic. Once the file has been generated, edit it, using the samples below as reference:

 

IPv4: 10.52.1.16

domain1.tld

domain2.tld

IPv4: 10.52.1.17

domain3.tld

 

Here, domains domain1.tld and domain2.tld will be assigned the IP address 10.52.1.16. Domain domain3.tld will be assigned the IP address 10.52.1.17.

 

IPv4: shared

domain1.tld

domain2.tld

 

Here, both domains will be assigned a shared IP address.

 

IPv4: dedicated

domain1.tld

domain2.tld

 

Here, each domain will be assigned a dedicated IP address chosen at random (there must be at least two unallocated dedicated IP addresses on the destination server).

 

IPv4: auto

domain1.tld

domain2.tld

 

Here, each domain will be assigned an IP address according to the automatic IP mapping rules.

 

IPv6: none

domain1.tld

domain2.tld

 

Here, no IPv6 address will be assigned to either domain; however, IPv4 addresses can still be assigned (as a domain cannot be created without an IP address).

 

You can use the migration list file to assign IPv6 IP addresses to domains, as well as IPv4 ones. Any domain can be assigned an IPv4 address, an IPv6 address, or both. When specifying IP address to assign to a domain, you can use a specific address, or the shared/dedicated/auto/none placeholders.

 

IPv4: 10.52.1.16

IPv6: 2002:5bcc:18fd:d:904c:9277:339a:ce56

domain1.tld

 

Here, the domain will be assigned both the IPv4 and the IPv6 addresses.

 

IP addresses assigned to resellers are propagated to all domains belonging to customer accounts under a specific reseller and the reseller's own domains.

 

Reseller: res1

IPv4: 10.52.1.16

domain1.tld

Customer: cust1

domain2.tld

Reseller: res2

domain3.tld

 

Here, domains domain1.tld and domain2.tld will be assigned the IP address 10.52.1.16, while the IP address for the domain domain3.tld will be assigned according to the automatic IP mapping rules.

 

 

 

 

 

 

 

Article sourced from Plesk Onyx

 

https://docs.plesk.com/en-US/onyx/migration-guide/ip-mapping.75658/