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// This is an example configuration file for DHCPv6 server in Kea.
// It demonstrates simple configuration of the options for a subnet.
{ "Dhcp6":
{
// Kea is told to listen on eth0 interface only.
"interfaces-config": {
"interfaces": [ "eth0" ]
},
// We need to specify the database used to store leases. As of
// June 2022, three database backends are supported: MySQL,
// PostgreSQL and the in-memory database, Memfile.
// We'll use memfile because it doesn't require any prior set up.
"lease-database": {
"type": "memfile"
},
// Addresses will be assigned with preferred and valid lifetimes
// being 3000 and 4000, respectively. Client is told to start
// renewing after 1000 seconds. If the server does not respond
// after 2000 seconds since the lease was granted, client is supposed
// to start REBIND procedure (emergency renewal that allows switching
// to a different server).
"preferred-lifetime": 3000,
"valid-lifetime": 4000,
"renew-timer": 1000,
"rebind-timer": 2000,
// Defining a subnet. There are some DHCP options returned to the
// clients connected to this subnet. The first option is identified
// by the name. The second option is identified by the code.
// There are two address pools defined within this subnet. Pool
// specific value for option 12 is defined for the pool:
// 2001:db8:1::1 - 2001:db8:1::100. Clients obtaining an address
// from this pool will be assigned option 12 with a value of
// 3001:cafe::21. Clients belonging to this subnet but obtaining
// addresses from the other pool, or the clients obtaining
// stateless configuration will be assigned subnet specific value
// of option 12, i.e. 2001:db8:1:0:ff00::1.
// For DHCPv6 subnets can have prefix delegation pools too so
// a pd-pools with an option-data is defined too.
"subnet6": [
{
// This is how option values are defined for this particular subnet.
"option-data": [
// When specifying options, you typically need to specify
// one of (name or code) and data. The full option specification
// covers name, code, space, csv-format and data.
// space defaults to "dhcp6" which is usually correct, unless you
// use encapsulate options. csv-format defaults to "true", so
// this is also correct, unless you want to specify the whole
// option value as long hex string. For example, to specify
// domain-name-servers you could do this:
// {
// "name": "dns-servers",
// "code": 23,
// "csv-format": true,
// "space": "dhcp6",
// "data": "2001:db8:2::45, 2001:db8:2::100"
// }
// but it's a lot of writing, so it's easier to do this instead:
{
"name": "dns-servers",
"data": "2001:db8:2::45, 2001:db8:2::100"
},
// Typically people prefer to refer to options by their
// names, so they don't need to remember the code
// names. However, some people like to use numerical
// values. For example, DHCPv6 can optionally use server
// unicast communication, if extra option is present. Option
// "unicast" uses option code 12, so you can reference to it
// either by "name": "unicast" or "code": 12.
{
"code": 12,
"data": "2001:db8:1:0:ff00::1"
},
// Options can also be specified using hexadecimal format.
// This should be avoided if possible, because Kea ability to
// validate correctness is limited when using hex values.
{
"name": "sntp-servers",
"csv-format": false,
"data": "20010db8000000000000000000000001"
},
// String options that have a comma in their values need to have
// it escaped (i.e. each comma is preceded by two backslashes).
// That's because commas are reserved for separating fields in
// compound options. At the same time, we need to be conformant
// with JSON spec, that does not allow "\,". Therefore the
// slightly uncommon double backslashes notation is needed.
// Legal JSON escapes are \ followed by "\/bfnrt character
// or \u followed by 4 hexa-decimal numbers (currently Kea
// supports only \u0000 to \u00ff code points).
// CSV processing translates '\\' into '\' and '\,' into ','
// only so for instance '\x' is translated into '\x'. But
// as it works on a JSON string value each of these '\'
// characters must be doubled on JSON input.
{
"name": "new-posix-timezone",
"data": "EST5EDT4\\,M3.2.0/02:00\\,M11.1.0/02:00"
},
// Options that take integer values can either be specified in
// dec or hex format. Hex format could be either plain (e.g. abcd)
// or prefixed with 0x (e.g. 0xabcd).
{
"name": "preference",
"data": "0xf0"
},
// A few options are encoded in (length, string) tuples
// which can be defined using only strings as the CSV
// processing computes lengths.
{
"name": "bootfile-param",
"data": "root=/dev/sda2, quiet, splash"
},
// At a few exceptions options are added to response only when
// the client requests them. The always-send flag should be used
// to enforce a particular option.
{
"name": "pana-agent",
"data": "2001:db8:2::123",
"always-send": true
}
],
"pools": [
{
"pool": "2001:db8:1::1 - 2001:db8:1::100",
"option-data": [
{
"code": 12,
"data": "3001:cafe::21"
}
]
},
{
"pool": "2001:db8:1::500 - 2001:db8:1::1000"
}
],
"pd-pools": [
{
"prefix": "2001:2b8:2::",
"prefix-len": 56,
"delegated-len": 64,
"option-data": [
{
"code": 12,
"data": "3001:cafe::12"
}
]
}
],
"id": 1,
"subnet": "2001:db8:1::/64",
"interface": "eth0"
}
],
// The following configures logging. It assumes that messages with at
// least informational level (info, warn, error and fatal) should be
// logged to stdout.
"loggers": [
{
"name": "kea-dhcp6",
"output-options": [
{
"output": "stdout"
}
],
"debuglevel": 0,
"severity": "INFO"
}
]
}
}
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