// DHCP client renews the lease.
"renew-timer": 30,
+ // Global value to store extended information (e.g. relay agent
+ // information) with each lease.
+ "store-extended-info:" true,
+
// Governs how the Kea DHCPv4 server should deal with the invalid
// data received from the client.
"sanity-checks": {
// network is selected for client assignments.
"require-client-classes": [ "late" ],
+ // Turn off storage of extended information (e.g. relay agent
+ // information) with each lease for this shared-network.
+ "store-extended-info:" false,
+
// Shared network level server hostname set in 'sname' field.
"server-hostname": "",
// in 'siaddr'.
"next-server": "0.0.0.0",
+ // Turn on storage of extended information (e.g. relay agent
+ // information) with each lease for this subnet.
+ "store-extended-info:" true,
+
// Subnet level list of DHCP options.
"option-data": [
{
// DHCP client renews the lease.
"renew-timer": 30,
+ // Global value to store extended information (e.g. relay agent
+ // information) with each lease.
+ "store-extended-info:" true,
+
// Governs how the Kea DHCPv6 server should deal with the invalid
// data received from the client.
"sanity-checks": {
// network is selected for client assignments.
"require-client-classes": [ "late" ],
+ // Turn off storage of extended information (e.g. relay agent
+ // information) with each lease for this shared-network.
+ "store-extended-info:" false,
+
// List of IPv6 subnets belonging to this shared network.
"subnet6": [
{
// which the response is sent.
"interface-id": "",
+ // Turn on storage of extended information (e.g. relay agent
+ // information) with each lease for this subnet.
+ "store-extended-info:" true,
+
// Subnet level list of DHCP options.
"option-data": [
{
...
}
+.. _dhcp4-store-extended-info:
+
+Storing Extended Lease Information
+----------------------------------
+In order to support such features as DHCP LeaseQuery
+(`RFC 4388 <https://tools.ietf.org/html/rfc4388>`__) it is necessary to
+store additional information with each lease. Because the amount
+of information stored for each lease has ramifications in terms of
+performance and system resource consumption, storing this additional
+information is configurable through the "store-extended-info" parameter.
+It defaults to false and may be set at the global, shared-network, and
+subnet levels.
+
+::
+
+ "Dhcp4": {
+ "store-extended-info": true,
+ ...
+ }
+
+When enabled, information relevant to the DHCPREQUEST asking for the lease is
+added into the lease's user-context as a map element labeled "ISC". Currently,
+the map will contain a single value, the relay-agent-info option (DHCP Option 82),
+when the DHCPREQUEST received contains it. Other values may be added at a
+future date. Since DHCPREQUESTs sent as renewals will likely not contain this
+information, the values taken from the last DHCPREQUEST that did contain it will
+be retained on the lease. The lease's user-context will look something like this:
+
+::
+
+ { "ISC": { "relay-agent-info": "0x52050104AABBCCDD" } }
+
+.. note::
+ This feature is intended to be used in conjunction with an upcoming LeaseQuery
+ hook library and at this time there is other use for this information within Kea.
+
+.. note::
+ It is possible that other hook libraries are already making use of user-context.
+ Enabling store-extended-info should not interfere with any other user-context
+ content so long as it does not also use an element labled "ISC". In other
+ words, user-context is intended to be a flexible container serving mulitple
+ purposes. As long as no other purpose also writes an "ISC" element to
+ user-contex there should not be a conflict.
+
.. _host-reservation-v4:
Host Reservation in DHCPv4
...
}
+.. _store-extended-info-v6:
+
+Storing Extended Lease Information
+----------------------------------
+In order to support such features as DHCPv6 Reconfigure
+(`RFC 3315 <https://tools.ietf.org/html/rfc3315>`__) and LeaseQuery
+(`RFC 5007 <https://tools.ietf.org/html/rfc5007>`__) it is necessary to
+store additional information with each lease. Because the amount
+of information stored for each lease has ramifications in terms of
+performance and system resource consumption, storing this additional
+information is configurable through the "store-extended-info" parameter.
+It defaults to false and may be set at the global, shared-network, and
+subnet levels.
+
+::
+
+ "Dhcp6": {
+ "store-extended-info": true,
+ ...
+ }
+
+When enabled, information relevant to the DHCPv6 query (e.g. REQUEST, RENEW,
+or REBIND) asking for the lease is added into the lease's user-context as a
+map element labeled "ISC". Currently the information contained in the map
+will be a list of relays, one for each relay message layer that encloses the
+client query. Other values may be added at a future date. The lease's
+user-context for a two-hop query might look something like this (shown
+pretty-printed for clarity):
+
+::
+
+ {
+ "ISC": {
+ "relays": [
+ {
+ "hop": 2,
+ "link": "2001:db8::1",
+ "peer": "2001:db8::2"
+ },
+ {
+ "hop": 1,
+ "link": "2001:db8::3",
+ "options": "0x00C800080102030405060708",
+ "peer": "2001:db8::4"
+ }]
+ }
+ }
+
+
+.. note::
+ This feature is intended to be used in conjunction with an upcoming
+ LeaseQuery hook library and at this time there is other use for this
+ information within Kea.
+
+.. note::
+ It is possible that other hook libraries are already making use of
+ user-context. Enabling store-extended-info should not interfere with
+ any other user-context content so long as it does not also use an element
+ labled "ISC". In other words, user-context is intended to be a flexible
+ container serving mulitple purposes. As long as no other purpose also
+ writes an "ISC" element to user-contex there should not be a conflict.
+
.. _host-reservation-v6:
Host Reservation in DHCPv6
projects / thirdparty / kea.git / commitdiff
