To transfer data between devices, they are combined into networks. An IP address is assigned to each device to identify it in the network. IP addresses are assigned according to IPv4 and IPv6 network protocol standards.
Each network consists of multiple IP addresses. One of them is the gateway for the others. Packets for devices in other networks are sent through the gateway. This allows to access devices from other networks.
The network can be broken down into blocks of IP addresses. IP address blocks are logically assembled into pools.
IP address networks
IPv4 addresses are usually written as four decimal numbers from 0 to 255 separated by dots. E.g., 192.168.0.3.
The bit mask determines the range of addresses included in the network. For example, the 255.255.255.0 mask for the network 10.0.0.0 indicates that this network consists of addresses from 10.0.0.0 to 10.0.0.255. Often the mask is written as a prefix to shorten the total recording. For example, mask 255.255.255.0 corresponds to the prefix /24.
The start address of an IPv4 network is called the network address and is used to identify it. The end address is called the broadcast address and is used to send data to all devices on the network. All other addresses can be assigned to the devices.
For example, the network 192.168.0.0/24 includes all addresses from 192.168.0.0 to 192.168.0.255. Devices in the network can be assigned addresses from 192.168.0.1 to 192.168.0.254.
An IPv6 address has the form of eight hexadecimal numbers separated by colons. E.g., 2001:0db8:85a3:0000:0000:8a2e:0370:7334.
The network prefix defines the range of addresses included in the network. For example, the record 2001:0db8:85a3:0001::/64 means that addresses from 2001:0db8:85a3:0001:0000:0000:0000 to 2001:0db8:85a3:0001:ffff:ffff:ffff are included into the network.
In contrast to IPv4 addresses, devices on a network can be assigned with all of its addresses, including the start and end addresses.
In DCImanager you can create an IPv6 network with prefix length from 0 to 64.
Blocks and pools of IP addresses
The physical network can be broken down into blocks. For example, the network 192.168.0.0/24 can be broken down into individual addresses (192.168.0.1), addresses by mask prefix (192.168.0.16/28) or address ranges (192.168.0.1-192.168.0.5).
IP address blocks are logically assembled into pools. For example, it is possible this way to divide the address blocks into public and private ones.
Using networks and pools in DCImanager
When adding a server, you need to select the pool from which the IP address will be given to it. This method of address assignment is called automatic. DCImanager will automatically select a free address from this pool. The address for the server can also be set manually, but it must be included in one of the created networks and be free.
You can select the pools to be used when ordering and releasing the server. Read more in Pools management.
In DCImanager, networks and pools are created separately for each location. The addresses of networks at different locations may overlap or be completely identical. This is because data centers can use the same networks with internal IP addresses.