[Kea-users] Dhcpv6 server
João Butzke
joao at naxi.com.br
Wed Mar 3 16:43:11 UTC 2021
Hi Joshua, thanks for the quick response.
The kea-dhcp6.conf file is in attachment.
There is no firewall in the server, when i perform a tcpdump in the
server interface it shows the dhcp packet requests, but there is no
response from the server.
There is no log when the client performs a solicit.
Best regards,
Joao Butzke.
On 03-Mar-21 12:38, Joshua Schaeffer wrote:
> On 3/3/21 7:41 AM, João Butzke wrote:
>> First of all, the server(ubuntu 20.04) need to have an ipv6 address
>> on the interface?
>
> Not necessarily. If you do not specify a unicast address in the
> configuration then kea-dhcp6 will listen on the multicast address for
> the VLAN that the interface resides on. The DHCPv6 multicast address
> is: ff02::1:2.
>
>> if yes, the address needs to be in the pool?
>
> Again, not necessarily. If you specify a unicast address that is not
> in the same subnet as your pool then you have to relay the DHCP
> requests to the server using DHCP relay.
>
>>
>> Here is the server log when started:
>>
>> naxi at dhcpv6:~/kea6$ 2021-03-02 20:42:09.551 INFO
>> [kea-dhcp6.hosts/6206.139941705381376] HOSTS_BACKENDS_REGISTERED the
>> following host backend types are available: mysql
>> 2021-03-02 20:42:09.554 INFO [kea-dhcp6.dhcpsrv/6206.139941705381376]
>> DHCPSRV_CFGMGR_ADD_IFACE listening on interface ens19
>> 2021-03-02 20:42:09.555 INFO [kea-dhcp6.dhcpsrv/6206.139941705381376]
>> DHCPSRV_CFGMGR_NEW_SUBNET6 a new subnet has been added to
>> configuration: 2804:15e4:8000::/36 with params: t1=1000, t2=2000,
>> preferred-lifetime=3000, valid-lifetime=4000, rapid-commit is false
>> 2021-03-02 20:42:09.556 INFO
>> [kea-dhcp6.commands/6206.139941705381376] COMMAND_ACCEPTOR_START
>> Starting to accept connections via unix domain socket bound to
>> /tmp/kea6-ctrl-socket
>> 2021-03-02 20:42:09.557 INFO [kea-dhcp6.dhcp6/6206.139941705381376]
>> DHCP6_CONFIG_COMPLETE DHCPv6 server has completed configuration:
>> added IPv6 subnets: 1; DDNS: disabled
>> 2021-03-02 20:42:09.557 INFO [kea-dhcp6.dhcpsrv/6206.139941705381376]
>> DHCPSRV_MYSQL_DB opening MySQL lease database: host=localhost
>> name=kea password=***** port=3306 type=mysql universe=6 user=kea
>> 2021-03-02 20:42:09.598 INFO [kea-dhcp6.hosts/6206.139941705381376]
>> DHCPSRV_MYSQL_HOST_DB opening MySQL hosts database: host=localhost
>> name=kea password=***** port=3306 type=mysql universe=6 user=kea
>> 2021-03-02 20:42:09.651 INFO [kea-dhcp6.dhcp6/6206.139941705381376]
>> DHCP6_USING_SERVERID server is using server-id
>> 00:01:00:01:27:cf:ff:37:16:41:55:fb:6b:16 and stores in the file
>> /usr/local/var/lib/kea/kea-dhcp6-serverid
>> 2021-03-02 20:42:09.655 WARN [kea-dhcp6.dhcp6/6206.139941705381376]
>> DHCP6_MULTI_THREADING_INFO enabled: no, number of threads: 0, queue
>> size: 0
>> 2021-03-02 20:42:09.655 INFO [kea-dhcp6.dhcp6/6206.139941705381376]
>> DHCP6_STARTED Kea DHCPv6 server version 1.8.2 started
>>
>> There is no errors, but when i run a tcdump, there is no answered
>> dhcp requests..
>
> I noticed you are configuring a /36. Do you have prefix delegation
> configured? You should provide your configuration. Also your log only
> shows up to kea starting. Are you getting any log entries when a
> client performs a SOLICIT? If not then your SOLICIT is not even
> getting to the server in the first place (or is being blocked by a
> firewall).
>
> --
> Thanks,
> Joshua Schaeffer
-------------- next part --------------
naxi at dhcpv6:/usr/local/etc/kea$ cat kea-dhcp6.conf
// This is a basic configuration for the Kea DHCPv6 server. Subnet declarations
// are mostly commented out and no interfaces are listed. Therefore, the servers
// will not listen or respond to any queries.
// The basic configuration must be extended to specify interfaces on which
// the servers should listen. There are a number of example options defined.
// These probably don't make any sense in your network. Make sure you at least
// update the following, before running this example in your network:
// - change the network interface names
// - change the subnets to match your actual network
// - change the option values to match your network
//
// This is just a very basic configuration. Kea comes with large suite (over 30)
// of configuration examples and extensive Kea User's Guide. Please refer to
// those materials to get better understanding of what this software is able to
// do. Comments in this configuration file sometimes refer to sections for more
// details. These are section numbers in Kea User's Guide. The version matching
// your software should come with your Kea package, but it is also available
// in ISC's Knowledgebase (https://kb.isc.org/docs/kea-administrator-reference-manual; the direct link for
// the stable version is https://kea.readthedocs.io/).
//
// This configuration file contains only DHCPv6 server's configuration.
// If configurations for other Kea services are also included in this file they
// are ignored by the DHCPv6 server.
{
// DHCPv6 configuration starts here. This section will be read by DHCPv6 server
// and will be ignored by other components.
"Dhcp6": {
// Add names of your network interfaces to listen on.
"interfaces-config": {
// You typically want to put specific interface names here, e.g. eth0
// but you can also specify unicast addresses (e.g. eth0/2001:db8::1) if
// you want your server to handle unicast traffic in addition to
// multicast. (DHCPv6 is a multicast based protocol).
"interfaces": ["ens19"],
"re-detect": false
},
// Kea support control channel, which is a way to receive management commands
// while the server is running. This is a Unix domain socket that receives
// commands formatted in JSON, e.g. config-set (which sets new configuration),
// config-reload (which tells Kea to reload its configuration from file),
// statistic-get (to retrieve statistics) and many more. For detailed
// description, see Sections 9.12, 16 and 15.
"control-socket": {
"socket-type": "unix",
"socket-name": "/tmp/kea6-ctrl-socket"
},
// Use Memfile lease database backend to store leases in a CSV file.
// Depending on how Kea was compiled, it may also support SQL databases
// (MySQL and/or PostgreSQL) and even Cassandra. Those database backends
// require more parameters, like name, host and possibly user and password.
// There are dedicated examples for each backend. See Section 8.2.2 "Lease
// Storage" for details.
"lease-database": {
"type": "mysql",
"name": "kea",
"user": "kea",
"password": "x",
"host": "localhost",
"port": 3306
},
// Kea allows storing host reservations in a database. If your network is
// small or you have few reservations, it's probably easier to keep them
// in the configuration file. If your network is large, it's usually better
// to use database for it. To enable it, uncomment the following:
"hosts-database": {
"type": "mysql",
"name": "kea",
"user": "kea",
"password": "x",
"host": "localhost",
"port": 3306
},
// See Section 8.2.3 "Hosts storage" for details.
// Setup reclamation of the expired leases and leases affinity.
// Expired leases will be reclaimed every 10 seconds. Every 25
// seconds reclaimed leases, which have expired more than 3600
// seconds ago, will be removed. The limits for leases reclamation
// are 100 leases or 250 ms for a single cycle. A warning message
// will be logged if there are still expired leases in the
// database after 5 consecutive reclamation cycles.
"expired-leases-processing": {
"reclaim-timer-wait-time": 10,
"flush-reclaimed-timer-wait-time": 25,
"hold-reclaimed-time": 3600,
"max-reclaim-leases": 100,
"max-reclaim-time": 250,
"unwarned-reclaim-cycles": 5
},
// These parameters govern global timers. 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, a client is
// supposed to start REBIND procedure (emergency renewal that allows
// switching to a different server).
"renew-timer": 1000,
"rebind-timer": 2000,
"preferred-lifetime": 3000,
"valid-lifetime": 4000,
// These are global options. They are going to be sent when a client requests
// them, unless overwritten with values in more specific scopes. The scope
// hierarchy is:
// - global
// - subnet
// - class
// - host
//
// Not all of those options make sense. Please configure only those that
// are actually useful in your network.
//
// For a complete list of options currently supported by Kea, see
// Section 8.2.9 "Standard DHCPv6 Options". Kea also supports
// vendor options (see Section 7.2.10) and allows users to define their
// own custom options (see Section 7.2.9).
"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": "2804:15e4:1::32:32, 2804:15e4:4::32:32"
}
// 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. If you enable this option,
// you really should also tell the server to listen on that address
// (see interfaces-config/interfaces list above).
# {
# "code": 12,
# "data": "2001:db8::1"
# },
// 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 hexadecimal 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"
# }
],
// Below an example of a simple IPv6 subnet declaration. Uncomment to enable
// it. This is a list, denoted with [ ], of structures, each denoted with
// { }. Each structure describes a single subnet and may have several
// parameters. One of those parameters is "pools" that is also a list of
// structures.
"subnet6": [
{
// This defines the whole subnet. Kea will use this information to
// determine where the clients are connected. This is the whole
// subnet in your network. This is mandatory parameter for each
// subnet.
"subnet": "2804:15e4:8000::/36",
// Pools define the actual part of your subnet that is governed
// by Kea. Technically this is optional parameter, but it's
// almost always needed for DHCP to do its job. If you omit it,
// clients won't be able to get addresses, unless there are
// host reservations defined for them.
# "pools": [ { "pool": "2804:15e4:8000::/36" } ],
// Kea supports prefix delegation (PD). This mechanism delegates
// whole prefixes, instead of single addresses. You need to specify
// a prefix and then size of the delegated prefixes that it will
// be split into. This example below tells Kea to use
// 2001:db8:1::/56 prefix as pool and split it into /64 prefixes.
// This will give you 256 (2^(64-56)) prefixes.
"pd-pools": [
{
"prefix": "2804:15e4:8000::",
"prefix-len": 36,
"delegated-len": 56
# "interface": "ens19"
}
],
"option-data": [
// You can specify additional options here that are subnet
// specific. Also, you can override global options here.
{
"name": "dns-servers",
"data": "2804:15e4:1::32:32, 2804:15e4:4::32:32"
}
],
// Host reservations can be defined for each subnet.
//
// Note that reservations are subnet-specific in Kea. This is
// different than ISC DHCP. Keep that in mind when migrating
// your configurations.
"reservations": [
// This is a simple host reservation. The host with DUID matching
// the specified value will get an address of 2001:db8:1::100.
#{
# "duid": "01:02:03:04:05:0A:0B:0C:0D:0E",
# "ip-addresses": [ "2001:db8:1:0::100" ]
#},
// This is similar to the previous one, but this time the
// reservation is done based on hardware/MAC address. The server
// will do its best to extract the hardware/MAC address from
// received packets (see 'mac-sources' directive for
// details). This particular reservation also specifies two
// extra options to be available for this client. If there are
// options with the same code specified in a global, subnet or
// class scope, the values defined at host level take
// precedence.
#{
# "hw-address": "00:01:02:03:04:05",
# "ip-addresses": [ "2001:db8:1:0::101" ],
# "option-data": [
# {
# "name": "dns-servers",
# "data": "3000:1::234"
# },
# {
# "name": "nis-servers",
# "data": "3000:1::234"
# }],
// This client will be automatically added to certain
// classes.
# "client-classes": [ "special_snowflake", "office" ]
#},
// This is a bit more advanced reservation. The client with the
// specified DUID will get a reserved address, a reserved prefix
// and a hostname. This reservation is for an address that it
// not within the dynamic pool. Finally, this reservation
// features vendor specific options for CableLabs, which happen
// to use enterprise-id 4491. Those particular values will be
// returned only to the client that has a DUID matching this
// reservation.
#{
# "duid": "01:02:03:04:05:06:07:08:09:0A",
# "ip-addresses": [ "2001:db8:1:0:cafe::1" ],
# "prefixes": [ "2001:db8:2:abcd::/64" ],
# "hostname": "foo.example.com",
# "option-data": [
# {
# "name": "vendor-opts",
# "data": "4491"
# },
# {
# "name": "tftp-servers",
# "space": "vendor-4491",
# "data": "3000:1::234"
# }
# ]
#},
// This reservation is using flexible identifier. Instead of
// relying on specific field, sysadmin can define an expression
// similar to what is used for client classification,
// e.g. substring(relay[0].option[17],0,6). Then, based on the
// value of that expression for incoming packet, the reservation
// is matched. Expression can be specified either as hex or
// plain text using single quotes.
// Note: flexible identifier requires flex_id hook library to be
// loaded to work.
#{
# "flex-id": "'somevalue'",
# "ip-addresses": [ "2001:db8:1:0:cafe::2" ]
#}
]
}
// More subnets can be defined here.
// {
// "subnet": "2001:db8:2::/64",
// "pools": [ { "pool": "2001:db8:2::/80" } ]
// },
// {
// "subnet": "2001:db8:3::/64",
// "pools": [ { "pool": "2001:db8:3::/80" } ]
// },
// {
// "subnet": "2001:db8:4::/64",
// "pools": [ { "pool": "2001:db8:4::/80" } ]
// }
],
// Client-classes can be defined here. See "client-classes" in Dhcp4 for
// an example.
// Hook libraries can be defined here. See "hooks-libraries" example in
// Dhcp4.
// DDNS information (how the DHCPv6 component can reach a DDNS daemon)
// Logging configuration starts here. Kea uses different loggers to log various
// activities. For details (e.g. names of loggers), see Chapter 18.
"loggers": [{
"name": "*",
"severity": "DEBUG",
"debuglevel": 99
}
]
}
}
naxi at dhcpv6:/usr/local/etc/kea$
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