reservation. Such a feature will be added in the upcoming Kea
releases.</para>
</section>
+
+ <section id="reservation4-mode">
+ <title>Fine Tuning IPv4 Host Reservation</title>
+
+ <note>
+ <para><command>reservation-mode</command> in DHCPv6 server in 0.9.1 beta is
+ accepted, but not used. Full implementation will be available in the upcoming
+ releases.</para>
+ </note>
+
+ <para>Host reservation capability introduces additional restrictions for the
+ allocation engine during lease selection and renewal. In particular, three
+ major checks are necessary. First, when selecting a new lease, it is not
+ sufficient for a candidate lease to be not used by anyone else. It also must
+ not be reserved for anyone else. Second, when renewing a lease, additional
+ check must be performed whether the address being renewed is not reserved
+ for anyone else. Finally, when a host renews an address, the server has to
+ check whether there's a reservation for this host, so the exisiting (dynamically
+ allocated) address should be revoked and the reserved one be used instead.
+ </para>
+ <para>Some of those checks in certain deployments may be not necessary. Skipping
+ them may improve performance. The Kea server allows configuration of the
+ reservation types allowed for each subnet using <command>reservation-mode</command>.
+ Allowed values are:
+
+ <itemizedlist>
+ <listitem><simpara> <command>all</command> - enables all host reservation
+ types. This is the default value. This setting is the safest and the most
+ flexible. It allows in-pool and out-of-pool reservations. As all checks
+ are conducted, it is also the slowest.
+ </simpara></listitem>
+
+ <listitem><simpara> <command>out-of-pool</command> - allows only out of
+ pool host reservations. With this setting in place, the server may assume
+ that all host reservations are for addresses that do not belong to the
+ dynamic pool. Therefore it can skip the reservation checks when dealing
+ with in-pool addresses, thus improving performance. Do not use this mode
+ if any of your reservations use in-pool address. Caution is advised when
+ using this setting. Kea 0.9.1 does not sanity check the reservations against
+ <command>reservation-mode</command>. Misconfiguration may cause problems.
+ </simpara></listitem>
+
+ <listitem><simpara>
+ <command>disabled</command> - host reservation support is disabled. As there
+ are no reservations, the server will skip all checks. Any reservations defined
+ will be completely ignored. As the checks are skipped, the server may
+ operate faster in this mode.
+ </simpara></listitem>
+
+ </itemizedlist>
+ </para>
+
+ <para>
+ An example configuration that disables reservation looks like follows:
+ <screen>
+"Dhcp4": {
+ "subnet4": [
+ "subnet": "192.0.2.0/24",
+ <userinput>"reservation-mode": "disabled"</userinput>,
+ ...
+ ]
+}
+</screen>
+ </para>
+ </section>
+
</section>
<!-- end of host reservations section -->
releases.</para>
</section>
+ <section id="reservation6-mode">
+ <title>Fine Tuning IPv6 Host Reservation</title>
+
+ <note>
+ <para><command>reservation-mode</command> in the DHCPv6 server in 0.9.1 beta is
+ implemented, but was not tested and is considered experimental.</para>
+ </note>
+
+ <para>Host reservation capability introduces additional restrictions for the
+ allocation engine during lease selection and renewal. In particular, three
+ major checks are necessary. First, when selecting a new lease, it is not
+ sufficient for a candidate lease to be not used by anyone else. It also must
+ not be reserved for anyone else. Second, when renewing a lease, additional
+ check must be performed whether the address being renewed is not reserved
+ for anyone else. Finally, when a host renews an address, the server has to
+ check whether there's a reservation for this host, so the exisiting (dynamically
+ allocated) address should be revoked and the reserved one be used instead.
+ </para>
+ <para>Some of those checks in certain deployments may be not necessary. Skipping
+ them may improve performance. The Kea server allows configuration of the
+ reservation types allowed for each subnet using <command>reservation-mode</command>.
+ Allowed values are:
+
+ <itemizedlist>
+ <listitem><simpara> <command>all</command> - enables all host reservation
+ types. This is the default value. This setting is the safest and the most
+ flexible. It allows in-pool and out-of-pool reservations. As all checks
+ are conducted, it is also the slowest.
+ </simpara></listitem>
+
+ <listitem><simpara> <command>out-of-pool</command> - allows only out of
+ pool host reservations. With this setting in place, the server may assume
+ that all host reservations are for addresses that do not belong to the
+ dynamic pool. Therefore it can skip the reservation checks when dealing
+ with in-pool addresses, thus improving performance. Do not use this mode
+ if any of your reservations use in-pool address. Caution is advised when
+ using this setting. Kea 0.9.1 does not sanity check the reservations against
+ <command>reservation-mode</command>. Misconfiguration may cause problems.
+ </simpara></listitem>
+
+ <listitem><simpara>
+ <command>disabled</command> - host reservation support is disabled. As there
+ are no reservations, the server will skip all checks. Any reservations defined
+ will be completely ignored. As the checks are skipped, the server may
+ operate faster in this mode.
+ </simpara></listitem>
+
+ </itemizedlist>
+ </para>
+
+ <para>
+ An example configuration that disables reservation looks like follows:
+ <screen>
+"Dhcp6": {
+ "subnet6": [
+ "subnet": "2001:db8:1::/64",
+ <userinput>"reservation-mode": "disabled"</userinput>,
+ ...
+ ]
+}
+</screen>
+ </para>
+ </section>
+
<!-- @todo: add support for per IA reservation (that specifies IAID in
the ip-addresses and prefixes) -->
</section>
"item_default": "0.0.0.0"
} ]
}
- } ]
+ },
+ {
+ "item_name": "reservation-mode",
+ "item_type": "string",
+ "item_optional": true,
+ "item_default": "all",
+ "item_description": "Specifies allowed host reservation types. Disabling unused modes may improve performance. Allowed values: disabled, off, out-of-pool, all"
+ }
+ ]
}
},
-// Copyright (C) 2012-2014 Internet Systems Consortium, Inc. ("ISC")
+// Copyright (C) 2012-2015 Internet Systems Consortium, Inc. ("ISC")
//
// Permission to use, copy, modify, and/or distribute this software for any
// purpose with or without fee is hereby granted, provided that the above
-// Copyright (C) 2012-2014 Internet Systems Consortium, Inc. ("ISC")
+// Copyright (C) 2012-2015 Internet Systems Consortium, Inc. ("ISC")
//
// Permission to use, copy, modify, and/or distribute this software for any
// purpose with or without fee is hereby granted, provided that the above
"\"subnet4\": [ { "
" \"pools\": [ { \"pool\": \"192.0.2.0/24\" } ],"
" \"subnet\": \"192.0.2.0/24\", "
- " \"reservation-mode\": \"all\","
- " \"interface\": \"eth0\""
+ " \"reservation-mode\": \"all\""
" },"
" {"
" \"pools\": [ { \"pool\": \"192.0.3.0/24\" } ],"
" \"subnet\": \"192.0.3.0/24\", "
- " \"reservation-mode\": \"out-of-pool\","
- " \"interface\": \"eth1\""
+ " \"reservation-mode\": \"out-of-pool\""
" },"
" {"
" \"pools\": [ { \"pool\": \"192.0.4.0/24\" } ],"
" \"subnet\": \"192.0.4.0/24\", "
- " \"reservation-mode\": \"disabled\","
- " \"interface\": \"eth1\""
+ " \"reservation-mode\": \"disabled\""
" },"
" {"
" \"pools\": [ { \"pool\": \"192.0.5.0/24\" } ],"
- " \"subnet\": \"192.0.5.0/24\", "
- " \"interface\": \"eth1\""
+ " \"subnet\": \"192.0.5.0/24\""
" } ],"
"\"valid-lifetime\": 4000 }";
ElementPtr json = Element::fromJSON(hr_config);
- CfgMgr::instance().clear();
ConstElementPtr result;
EXPECT_NO_THROW(result = configureDhcp4Server(*srv_, json));
}
} ]
}
+ },
+ {
+ "item_name": "reservation-mode",
+ "item_type": "string",
+ "item_optional": true,
+ "item_default": "all",
+ "item_description": "Specifies allowed host reservation types. Disabling unused modes may improve performance. Allowed values: disabled, off, out-of-pool, all"
} ]
}
},
hints_count++;
}
- // If this is a Renew, it's ok to allocate new leases
+ /// @todo: This was clarfied in draft-ietf-dhc-dhcpv6-stateful-issues that
+ /// the server is allowed to assign new leases in both Renew and Rebind. For
+ /// now, we only support it in Renew, because it breaks a lot of Rebind
+ /// unit-tests. Ultimately, whether we allow it or not, should be exposed
+ /// as configurable policy. See ticket #3717.
if (query->getType() == DHCPV6_RENEW) {
ctx.allow_new_leases_in_renewals_ = true;
}
+
Lease6Collection leases = alloc_engine_->renewLeases6(ctx);
// Ok, now we have the leases extended. We have:
hints_count++;
}
+ /// @todo: The draft-ietf-dhc-dhcpv6-stateful-issues added a new capability
+ /// of the server to to assign new PD leases in both Renew and Rebind.
+ /// There's allow_new_leases_in_renewals_ in the ClientContext6, but we
+ /// currently not use it in PD yet. This should be implemented as part
+ /// of the stateful-issues implementation effort. See ticket #3718.
+
// Call Allocation Engine and attempt to renew leases. Number of things
// may happen. Leases may be extended, revoked (if the lease is no longer
// valid or reserved for someone else), or new leases may be added.
-// Copyright (C) 2011-2014 Internet Systems Consortium, Inc. ("ISC")
+// Copyright (C) 2011-2015 Internet Systems Consortium, Inc. ("ISC")
//
// Permission to use, copy, modify, and/or distribute this software for any
// purpose with or without fee is hereby granted, provided that the above
-// Copyright (C) 2012-2014 Internet Systems Consortium, Inc. ("ISC")
+// Copyright (C) 2012-2015 Internet Systems Consortium, Inc. ("ISC")
//
// Permission to use, copy, modify, and/or distribute this software for any
// purpose with or without fee is hereby granted, provided that the above
"\"subnet6\": [ { "
" \"pools\": [ { \"pool\": \"2001:db8:1::/64\" } ],"
" \"subnet\": \"2001:db8:1::/48\", "
- " \"reservation-mode\": \"all\","
- " \"interface\": \"eth0\""
+ " \"reservation-mode\": \"all\""
" },"
" {"
" \"pools\": [ { \"pool\": \"2001:db8:2::/64\" } ],"
" \"subnet\": \"2001:db8:2::/48\", "
- " \"reservation-mode\": \"out-of-pool\","
- " \"interface\": \"eth1\""
+ " \"reservation-mode\": \"out-of-pool\""
" },"
" {"
" \"pools\": [ { \"pool\": \"2001:db8:3::/64\" } ],"
" \"subnet\": \"2001:db8:3::/48\", "
- " \"reservation-mode\": \"disabled\","
- " \"interface\": \"eth1\""
+ " \"reservation-mode\": \"disabled\""
" },"
" {"
" \"pools\": [ { \"pool\": \"2001:db8:4::/64\" } ],"
- " \"subnet\": \"2001:db8:4::/48\", "
- " \"interface\": \"eth1\""
+ " \"subnet\": \"2001:db8:4::/48\" "
" } ],"
"\"valid-lifetime\": 4000 }";
checkResult(status, 0);
CfgMgr::instance().commit();
- const Subnet6Collection* subnets =
- CfgMgr::instance().getCurrentCfg()->getCfgSubnets6()->getAll();
+ ConstCfgSubnets6Ptr subnets = CfgMgr::instance().getCurrentCfg()->getCfgSubnets6();
+
+ const Subnet6Collection* subnet_col = subnets->getAll();
ASSERT_TRUE(subnets);
- ASSERT_EQ(4, subnets->size()); // We expect 4 subnets
+ ASSERT_EQ(4, subnet_col->size()); // We expect 4 subnets
+
+ // Let's check if the parsed subnets have correct HR modes
+ Subnet6Ptr subnet;
+ subnet = subnets->selectSubnet(IOAddress("2001:db8:1::1"));
+ ASSERT_TRUE(subnet);
+ EXPECT_EQ(Subnet::HR_ALL, subnet->getHostReservationMode());
- // Check subnet-ids of each subnet (it should be monotonously increasing)
- EXPECT_EQ(Subnet::HR_ALL, subnets->at(0)->getHostReservationMode());
- EXPECT_EQ(Subnet::HR_OUT_OF_POOL, subnets->at(1)->getHostReservationMode());
- EXPECT_EQ(Subnet::HR_DISABLED, subnets->at(2)->getHostReservationMode());
- EXPECT_EQ(Subnet::HR_ALL, subnets->at(3)->getHostReservationMode());
+
+ subnet = subnets->selectSubnet(IOAddress("2001:db8:2::1"));
+ ASSERT_TRUE(subnet);
+ EXPECT_EQ(Subnet::HR_OUT_OF_POOL, subnet->getHostReservationMode());
+
+ subnet = subnets->selectSubnet(IOAddress("2001:db8:3::1"));
+ ASSERT_TRUE(subnet);
+ EXPECT_EQ(Subnet::HR_DISABLED, subnet->getHostReservationMode());
+
+ subnet = subnets->selectSubnet(IOAddress("2001:db8:4::1"));
+ ASSERT_TRUE(subnet);
+ EXPECT_EQ(Subnet::HR_ALL, subnet->getHostReservationMode());
}
};
-// Copyright (C) 2013-2014 Internet Systems Consortium, Inc. ("ISC")
+// Copyright (C) 2013-2015 Internet Systems Consortium, Inc. ("ISC")
//
// Permission to use, copy, modify, and/or distribute this software for any
// purpose with or without fee is hereby granted, provided that the above
-// Copyright (C) 2013-2014 Internet Systems Consortium, Inc. ("ISC")
+// Copyright (C) 2013-2015 Internet Systems Consortium, Inc. ("ISC")
//
// Permission to use, copy, modify, and/or distribute this software for any
// purpose with or without fee is hereby granted, provided that the above
-// Copyright (C) 2013-2014 Internet Systems Consortium, Inc. ("ISC")
+// Copyright (C) 2013-2015 Internet Systems Consortium, Inc. ("ISC")
//
// Permission to use, copy, modify, and/or distribute this software for any
// purpose with or without fee is hereby granted, provided that the above
}
Subnet::HRMode
-HRModeFromText(const std::string& txt) {
+SubnetConfigParser::hrModeFromText(const std::string& txt) {
if ( (txt.compare("disabled") == 0) ||
(txt.compare("off") == 0) ) {
return (Subnet::HR_DISABLED);
// iface not mandatory so swallow the exception
}
- std::string hr_mode;
- try {
- hr_mode = string_values_->getParam("reservation-mode");
- } catch (const DhcpConfigError &) {
- // Host reservation mode is not mandatory, so don't complain
- }
+ // Let's set host reservation mode. If not specified, the default value of
+ // all will be used.
+ std::string hr_mode;
try {
- // This may throw if the user didn't specify one of allowed values
- if (!hr_mode.empty()) {
- subnet_->setHostReservationMode(HRModeFromText(hr_mode));
- }
+ hr_mode = string_values_->getOptionalParam("reservation-mode", "all");
+ subnet_->setHostReservationMode(hrModeFromText(hr_mode));
} catch (const BadValue& ex) {
isc_throw(DhcpConfigError, "Failed to process specified value "
" of reservation-mode parameter: " << ex.what()
/// unspecified value.
isc::dhcp::Triplet<uint32_t> getOptionalParam(const std::string& name);
+ /// @brief Attempts to convert text representation to HRMode enum.
+ ///
+ /// Allowed values are "disabled", "off" (alias for disabled),
+ /// "out-of-pool" and "all". See Subnet::HRMode for their exact meaning.
+ ///
+ /// @throw BadValue if the text cannot be converted.
+ ///
+ /// @param text representation for conversion
+ /// @return one of allowed HRMode values
+ static Subnet::HRMode hrModeFromText(const std::string& txt);
+
private:
/// @brief Create a new subnet using a data from child parsers.
///
/// @return whether in-pool host reservations are allowed.
HRMode
- getHostReservationMode() {
+ getHostReservationMode() const {
return (host_reservation_mode_);
}
host_reservation_mode_ = mode;
}
- /// @brief Attempts to convert text representation to HRMode enum
- ///
- /// @throw BadValue if the text cannot be converted
- ///
- /// @param text representation for conversion
- /// @return one of allowed HRMode values
- static HRMode HRModeFromText(const std::string& txt);
-
protected:
/// @brief Returns all pools (non-const variant)
///
}
DuidPtr duid_; ///< client-identifier (value used in tests)
- HWAddrPtr hwaddr_; ///< client's hardware address
+ HWAddrPtr hwaddr_; ///< client's hardware address
uint32_t iaid_; ///< IA identifier (value used in tests)
Subnet6Ptr subnet_; ///< subnet6 (used in tests)
Pool6Ptr pool_; ///< NA pool belonging to subnet_
-// Copyright (C) 2014 Internet Systems Consortium, Inc. ("ISC")
+// Copyright (C) 2014-2015 Internet Systems Consortium, Inc. ("ISC")
//
// Permission to use, copy, modify, and/or distribute this software for any
// purpose with or without fee is hereby granted, provided that the above
-// Copyright (C) 2012-2014 Internet Systems Consortium, Inc. ("ISC")
+// Copyright (C) 2012-2015 Internet Systems Consortium, Inc. ("ISC")
//
// Permission to use, copy, modify, and/or distribute this software for any
// purpose with or without fee is hereby granted, provided that the above
projects / thirdparty / kea.git / commitdiff
