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// This is an example configuration file for DHCPv4 server in Kea.
// It demonstrates an advanced feature called shared network. Typically, for
// each physical link there is one IPv4 subnet that the server is expected
// to manage. However, in some cases there is a need to configure more subnets
// in the same physical location. The most common use case is an existing
// subnet that grew past its original assumptions and ran out of addresses,
// so the sysadmin needs to add another subnet on top of existing one.
{
"Dhcp4": {
// As with any other configuration, you need to tell Kea the interface
// names, so it would listen to incoming traffic.
"interfaces-config": {
"interfaces": [ "eth0" ]
},
// You also need to tell where to store lease information.
// memfile is the backend that is easiest to set up.
"lease-database": {
"type": "memfile",
"lfc-interval": 3600
},
// The shared networks definition starts here. shared-networks can
// contain a list of shared networks. There are many parameters
// that can be specified here, so this example may be overwhelming
// at first, but the only mandatory parameter for each shared
// network is name. It must be unique. Typically, each shared
// network also needs to have at least two subnets to be functional,
// but if you really want to, you can define a degraded shared
// network that has 1 or even 0 subnets. This may come in handy
// when migrating between regular subnets and shared networks
// or when debugging a problem. It is not recommended to use
// 1 subnet per shared network, as there is extra processing
// overhead for shared networks.
"shared-networks": [
{
// Name of the shared network. It may be an arbitrary string
// and it must be unique among all shared networks.
"name": "frog",
// You may specify interface name if the shared network is
// reachable directly from the server.
"interface": "eth1",
// You can specify many parameters that are allowed in subnet scope
// here. It's useful to put them here if they apply to all subnets
// in this shared network. It's likely that the most common
// parameter here will be option values defined with option-data.
"match-client-id": false,
"option-data": [ ],
"rebind-timer": 150,
"authoritative": true,
// If all the traffic coming from that shared network is reachable
// via relay and that relay always use the same IP address, you
// can specify that relay address here. Since this example shows
// a shared network reachable directly, we put 0.0.0.0 here.
// It would be better to skip the relay scope altogether, but
// it was left here for demonstration purposes.
"relay": {
"ip-addresses": [ "0.0.0.0" ]
},
// Timer values can be overridden here.
"renew-timer": 100,
// Specify whether the server should look up global reservations.
"reservations-global": false,
// Specify whether the server should look up in-subnet reservations.
"reservations-in-subnet": true,
// Specify whether the server can assume that all reserved addresses
// are out-of-pool.
// Ignored when reservations-in-subnet is false.
// If specified, it is inherited by "subnet4" levels.
"reservations-out-of-pool": false,
// This starts a list of subnets allowed in this shared network.
// In our example, there are two subnets.
"subnet4": [
{
"id": 1,
"match-client-id": true,
"next-server": "0.0.0.0",
"server-hostname": "",
"boot-file-name": "",
"option-data": [ ],
"pools": [ ],
"rebind-timer": 20,
// You can override the value inherited from shared-network
// here if your relay uses different IP addresses for
// each subnet.
"relay": {
"ip-addresses": [ "0.0.0.0" ]
},
"renew-timer": 10,
// Specify whether the server should look up global reservations.
"reservations-global": false,
// Specify whether the server should look up in-subnet reservations.
"reservations-in-subnet": true,
// Specify whether the server can assume that all reserved addresses
// are out-of-pool.
// Ignored when reservations-in-subnet is false.
"reservations-out-of-pool": false,
"subnet": "10.0.0.0/8",
"valid-lifetime": 30
},
{
"id": 2,
"match-client-id": true,
"next-server": "0.0.0.0",
"server-hostname": "",
"boot-file-name": "",
"option-data": [ ],
"pools": [ ],
"rebind-timer": 20,
"renew-timer": 10,
// Specify whether the server should look up global reservations.
"reservations-global": false,
// Specify whether the server should look up in-subnet reservations.
"reservations-in-subnet": true,
// Specify whether the server can assume that all reserved addresses
// are out-of-pool.
// Ignored when reservations-in-subnet is false.
"reservations-out-of-pool": false,
"subnet": "192.0.2.0/24",
"valid-lifetime": 30
}
],
"valid-lifetime": 200
} ], // end of shared-networks
// It is likely that in your network you'll have a mix of regular,
// "plain" subnets and shared networks. It is perfectly valid to mix
// them in the same config file.
// This is regular subnet. It's not part of any shared-network.
"subnet4": [
{
"pools": [ { "pool": "192.0.3.1 - 192.0.3.200" } ],
"subnet": "192.0.3.0/24",
"interface": "eth0",
"id": 3
}
]
} // end of Dhcp4
}
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