Kea 2.7.4
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DHCPv4 and DHCPv6 allocation engine. More...
#include <alloc_engine.h>
Classes | |
struct | ClientContext4 |
Context information for the DHCPv4 lease allocation. More... | |
struct | ClientContext6 |
Context information for the DHCPv6 leases allocation. More... | |
class | Resource |
Defines a single hint. More... | |
struct | ResourceCompare |
Resource compare class. More... | |
Public Types | |
typedef boost::shared_ptr< ClientContext4 > | ClientContext4Ptr |
Pointer to the ClientContext4 . | |
typedef std::vector< Resource > | HintContainer |
Container for client's hints. | |
typedef std::list< IdentifierPair > | IdentifierList |
Map holding values to be used as host identifiers. | |
typedef std::pair< Host::IdentifierType, std::vector< uint8_t > > | IdentifierPair |
A tuple holding host identifier type and value. | |
typedef std::set< Resource, ResourceCompare > | ResourceContainer |
Container holding allocated prefixes or addresses. | |
Public Member Functions | |
AllocEngine (isc::util::uint128_t const &attempts) | |
Constructor. | |
virtual | ~AllocEngine () |
Destructor. | |
Lease4Ptr | allocateLease4 (ClientContext4 &ctx) |
Returns IPv4 lease. | |
Lease6Collection | allocateLeases6 (ClientContext6 &ctx) |
Allocates IPv6 leases for a given IA container. | |
void | deleteExpiredReclaimedLeases4 (const uint32_t secs) |
Deletes reclaimed leases expired more than specified amount of time ago. | |
void | deleteExpiredReclaimedLeases6 (const uint32_t secs) |
Deletes reclaimed leases expired more than specified amount of time ago. | |
isc::util::ReadWriteMutex & | getReadWriteMutex () |
Get the read-write mutex. | |
void | reclaimExpiredLeases4 (const size_t max_leases, const uint16_t timeout, const bool remove_lease, const uint16_t max_unwarned_cycles=0) |
Reclaims expired IPv4 leases. | |
void | reclaimExpiredLeases4Internal (const size_t max_leases, const uint16_t timeout, const bool remove_lease, const uint16_t max_unwarned_cycles=0) |
Body of reclaimExpiredLeases4. | |
void | reclaimExpiredLeases6 (const size_t max_leases, const uint16_t timeout, const bool remove_lease, const uint16_t max_unwarned_cycles=0) |
Reclaims expired IPv6 leases. | |
void | reclaimExpiredLeases6Internal (const size_t max_leases, const uint16_t timeout, const bool remove_lease, const uint16_t max_unwarned_cycles=0) |
Body of reclaimExpiredLeases6. | |
Lease6Collection | renewLeases6 (ClientContext6 &ctx) |
Renews existing DHCPv6 leases for a given IA. | |
Static Public Member Functions | |
static ConstHostPtr | findGlobalReservation (ClientContext4 &ctx) |
Attempts to find the host reservation for the client. | |
static ConstHostPtr | findGlobalReservation (ClientContext6 &ctx) |
Attempts to find the host reservation for the client. | |
static void | findReservation (ClientContext4 &ctx) |
Attempts to find the host reservation for the client. | |
static void | findReservation (ClientContext6 &ctx) |
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static void | getLifetimes6 (ClientContext6 &ctx, uint32_t &preferred, uint32_t &valid) |
Determines the preferred and valid v6 lease lifetimes. | |
static uint32_t | getOfferLft (const ClientContext4 &ctx) |
Returns the offer lifetime based on the v4 context. | |
static uint32_t | getValidLft (const ClientContext4 &ctx) |
Returns the valid lifetime based on the v4 context. | |
static std::string | labelNetworkOrSubnet (SubnetPtr subnet) |
Generates a label for subnet or shared-network from subnet. | |
static IPv6Resrv | makeIPv6Resrv (const Lease6 &lease) |
Creates an IPv6Resrv instance from a Lease6. | |
Public Attributes | |
isc::util::ReadWriteMutex | rw_mutex_ |
The read-write mutex. | |
Protected Member Functions | |
void | clearReclaimedExtendedInfo (const Lease4Ptr &lease) const |
Clear extended info from a reclaimed V4 lease. | |
void | clearReclaimedExtendedInfo (const Lease6Ptr &lease) const |
Clear extended info from a reclaimed V6 lease. | |
bool | updateLease4ExtendedInfo (const Lease4Ptr &lease, const ClientContext4 &ctx) const |
Stores additional client query parameters on a V4 lease. | |
void | updateLease6ExtendedInfo (const Lease6Ptr &lease, const ClientContext6 &ctx) const |
Stores additional client query parameters on a V6 lease. | |
DHCPv4 and DHCPv6 allocation engine.
This class represents a DHCP allocation engine. It is responsible for picking subnets, choosing and allocating a lease, extending, renewing, releasing and possibly expiring leases.
Definition at line 47 of file alloc_engine.h.
typedef boost::shared_ptr<ClientContext4> isc::dhcp::AllocEngine::ClientContext4Ptr |
Pointer to the ClientContext4
.
Definition at line 1378 of file alloc_engine.h.
typedef std::vector<Resource> isc::dhcp::AllocEngine::HintContainer |
Container for client's hints.
Definition at line 185 of file alloc_engine.h.
typedef std::list<IdentifierPair> isc::dhcp::AllocEngine::IdentifierList |
Map holding values to be used as host identifiers.
Definition at line 194 of file alloc_engine.h.
typedef std::pair<Host::IdentifierType, std::vector<uint8_t> > isc::dhcp::AllocEngine::IdentifierPair |
A tuple holding host identifier type and value.
Definition at line 191 of file alloc_engine.h.
typedef std::set<Resource, ResourceCompare> isc::dhcp::AllocEngine::ResourceContainer |
Container holding allocated prefixes or addresses.
Definition at line 188 of file alloc_engine.h.
isc::dhcp::AllocEngine::AllocEngine | ( | isc::util::uint128_t const & | attempts | ) |
Constructor.
Instantiates necessary services, required to run DHCP server. In particular, creates IfaceMgr that will be responsible for network interaction. Will instantiate lease manager, and load old or create new DUID.
attempts | number of attempts for each lease allocation before we give up (0 means unlimited) |
Definition at line 94 of file alloc_engine.cc.
References Hooks.
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Destructor.
Definition at line 62 of file alloc_engine.h.
Lease4Ptr isc::dhcp::AllocEngine::allocateLease4 | ( | ClientContext4 & | ctx | ) |
Returns IPv4 lease.
This method finds a lease for a client using the following algorithm:
The lease allocation process is slightly different for the DHCPDISCOVER and DHCPREQUEST messages. In the former case, the client may specify the requested IP address option with a desired address and the server treats this address as a hint. This means that the server may allocate a different address at its discretion and send it to the client in the DHCPOFFER. If the client accepts this offer it specifies this address in the requested IP address option in the DHCPREQUEST. At this point, the allocation engine will use the requested IP address as a hard requirement and if this address can't be allocated for any reason, the allocation engine returns NULL lease. As a result, the DHCP server sends a DHCPNAK to the client and the client falls back to the DHCP server discovery.
The only exception from this rule is when the client doesn't specify a requested IP address option (invalid behavior) in which case the allocation engine will try to allocate any address.
If there is an address reservation specified for the particular client the reserved address always takes precedence over addresses from the dynamic pool or even an address currently allocated for this client.
It is possible that the address reserved for the particular client is in use by another client, e.g. as a result of pools reconfiguration. In this case, when the client requests allocation of the reserved address and the server determines that it is leased to someone else, the allocation engine allocates a different address for this client.
When the client having a lease returns to renew, the allocation engine doesn't extend the lease for it and returns a NULL pointer. The client falls back to the 4-way exchange and a different lease is allocated. At this point, the reserved address is freed and can be allocated to the client which holds this reservation. However, this client has a lease for a different address at this time. When the client renews its lease it receives the DHCPNAK and falls back to the DHCP server discovery and obtains the lease for the reserved address.
When a server should do DNS updates, it is required that allocation returns the information about how the lease was obtained by the allocation engine. In particular, the DHCP server should be able to check whether an existing lease was returned, or a new lease was allocated. When an existing lease was returned, the server should check whether the FQDN has changed between the allocation of the old and new lease. If so, the server should perform the appropriate DNS update. If not, the server may choose to not perform the update. The information about the old lease is returned via old_lease
parameter. If NULL value is returned, it is an indication that a new lease was allocated for the client. If non-NULL value is returned, it is an indication that allocation engine reused/renewed an existing lease.
ctx | client context that passes all necessary information. See ClientContext4 for details. |
The following fields of ClientContext4 are used:
Definition at line 3684 of file alloc_engine.cc.
References isc::dhcp::alloc_engine_logger, isc::dhcp::ALLOC_ENGINE_V4_ALLOC_ERROR, isc::dhcp::AllocEngine::ClientContext4::fake_allocation_, isc::dhcp::AllocEngine::ClientContext4::hwaddr_, isc_throw, LOG_ERROR, isc::dhcp::AllocEngine::ClientContext4::new_lease_, isc::dhcp::AllocEngine::ClientContext4::old_lease_, isc::dhcp::AllocEngine::ClientContext4::query_, and isc::dhcp::AllocEngine::ClientContext4::subnet_.
Lease6Collection isc::dhcp::AllocEngine::allocateLeases6 | ( | ClientContext6 & | ctx | ) |
Allocates IPv6 leases for a given IA container.
This method uses the currently selected allocator to pick allocable resources (i.e. addresses or prefixes) from specified subnet, creates a lease (one or more, if needed) for that resources and then inserts it into LeaseMgr (if this allocation is not fake, i.e. this is not a response to SOLICIT).
This method uses host reservation if ClientContext6::hosts_ is set. The easy way to set it is to call findReservationDecl. The host reservation is convenient, but incurs performance penalty, so it can be tweaked on a per subnet basis. There are three possible modes:
The logic in this method is as follows:
ctx | client context that passes all necessary information. See ClientContext6 for details. |
The following fields of ClientContext6 are used:
ClientContext6::subnet_ subnet the allocation should come from
ClientContext6::duid_ Client's DUID
ClientContext6::IAContext::iaid_ iaid field from the IA_NA container that client sent
ClientContext6::IAContext::hints_ a hint that the client provided
ClientContext6::IAContext::type_ lease type (IA, TA or PD)
ClientContext6::fwd_dns_update_ A boolean value which indicates that server takes responsibility for the forward DNS Update for this lease (if true).
ClientContext6::rev_dns_update_ A boolean value which indicates that server takes responsibility for the reverse DNS Update for this lease (if true).
ClientContext6::hostname_ A fully qualified domain-name of the client.
ClientContext6::fake_allocation_ is this real i.e. REQUEST (false) or just picking an address for SOLICIT that is not really allocated (true)
ClientContext6::callout_handle_ a callout handle (used in hooks). A lease callouts will be executed if this parameter is passed.
ClientContext6::IAContext::old_leases_ [out] Collection to which this function will append old leases. Leases are stored in the same order as in the collection of new leases, being returned. For newly allocated leases (not renewed) the NULL pointers are stored in this collection as old leases.
ClientContext6::hwaddr_ Hardware address (optional, may be null if not available)
ClientContext6::hosts_ Host reservations. allocateLeases6 will set this field, if appropriate reservations are found.
Definition at line 461 of file alloc_engine.cc.
References isc::dhcp::AllocEngine::ClientContext6::addAllocatedResource(), isc::dhcp::ALLOC_ENGINE_DBG_TRACE, isc::dhcp::alloc_engine_logger, isc::dhcp::ALLOC_ENGINE_V6_ALLOC_ERROR, isc::dhcp::ALLOC_ENGINE_V6_ALLOC_LEASES_HR, isc::dhcp::ALLOC_ENGINE_V6_ALLOC_LEASES_NO_HR, isc::dhcp::ALLOC_ENGINE_V6_ALLOC_NO_LEASES_HR, isc::dhcp::ALLOC_ENGINE_V6_ALLOC_UNRESERVED, isc::dhcp::AllocEngine::ClientContext6::currentIA(), isc::dhcp::AllocEngine::ClientContext6::duid_, isc::dhcp::AllocEngine::ClientContext6::hosts_, isc::dhcp::AllocEngine::ClientContext6::IAContext::iaid_, isc::dhcp::LeaseMgrFactory::instance(), isc_throw, LOG_DEBUG, LOG_ERROR, isc::dhcp::AllocEngine::ClientContext6::new_leases_, isc::dhcp::AllocEngine::ClientContext6::query_, isc::dhcp::AllocEngine::ClientContext6::subnet_, and isc::dhcp::AllocEngine::ClientContext6::IAContext::type_.
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Clear extended info from a reclaimed V4 lease.
[out] | lease | A pointer to the reclaimed lease. |
Definition at line 3258 of file alloc_engine.cc.
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Clear extended info from a reclaimed V6 lease.
[out] | lease | A pointer to the reclaimed lease. |
Definition at line 3267 of file alloc_engine.cc.
References isc::dhcp::Lease6::ACTION_DELETE.
void isc::dhcp::AllocEngine::deleteExpiredReclaimedLeases4 | ( | const uint32_t | secs | ) |
Deletes reclaimed leases expired more than specified amount of time ago.
secs | Minimum number of seconds after which the lease can be deleted. |
Definition at line 3091 of file alloc_engine.cc.
References isc::dhcp::ALLOC_ENGINE_DBG_TRACE, isc::dhcp::alloc_engine_logger, isc::dhcp::ALLOC_ENGINE_V4_RECLAIMED_LEASES_DELETE, isc::dhcp::ALLOC_ENGINE_V4_RECLAIMED_LEASES_DELETE_COMPLETE, isc::dhcp::ALLOC_ENGINE_V4_RECLAIMED_LEASES_DELETE_FAILED, isc::dhcp::LeaseMgrFactory::instance(), LOG_DEBUG, and LOG_ERROR.
void isc::dhcp::AllocEngine::deleteExpiredReclaimedLeases6 | ( | const uint32_t | secs | ) |
Deletes reclaimed leases expired more than specified amount of time ago.
secs | Minimum number of seconds after which the lease can be deleted. |
Definition at line 2658 of file alloc_engine.cc.
References isc::dhcp::ALLOC_ENGINE_DBG_TRACE, isc::dhcp::alloc_engine_logger, isc::dhcp::ALLOC_ENGINE_V6_RECLAIMED_LEASES_DELETE, isc::dhcp::ALLOC_ENGINE_V6_RECLAIMED_LEASES_DELETE_COMPLETE, isc::dhcp::ALLOC_ENGINE_V6_RECLAIMED_LEASES_DELETE_FAILED, isc::dhcp::LeaseMgrFactory::instance(), LOG_DEBUG, and LOG_ERROR.
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Attempts to find the host reservation for the client.
This method attempts to find a "global" host reservation matching the client identifier. It will return the first global reservation that matches per the configured list of host identifiers, or an empty pointer if no matches are found.
ctx | Client context holding various information about the client. |
Definition at line 3831 of file alloc_engine.cc.
References isc::dhcp::AllocEngine::ClientContext4::host_identifiers_, and isc::dhcp::HostMgr::instance().
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Attempts to find the host reservation for the client.
This method attempts to find a "global" host reservation matching the client identifier. It will return the first global reservation that matches per the configured list of host identifiers, or an empty pointer if no matches are found.
ctx | Client context holding various information about the client. |
Definition at line 444 of file alloc_engine.cc.
References isc::dhcp::AllocEngine::ClientContext6::host_identifiers_, and isc::dhcp::HostMgr::instance().
Referenced by findReservation(), and findReservation().
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Attempts to find the host reservation for the client.
Attempts to find appropriate host reservation in HostMgr. If found, it is set in the ClientContext4::hosts_.
ctx | Client context holding various information about the client. |
Definition at line 3728 of file alloc_engine.cc.
References isc::dhcp::AllocEngine::ClientContext4::early_global_reservations_lookup_, findGlobalReservation(), isc::dhcp::AllocEngine::ClientContext4::host_identifiers_, isc::dhcp::AllocEngine::ClientContext4::hosts_, isc::dhcp::HostMgr::instance(), isc::dhcp::AllocEngine::ClientContext4::query_, and isc::dhcp::AllocEngine::ClientContext4::subnet_.
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Attempts to find appropriate host reservation.
Attempts to find appropriate host reservation in HostMgr. If found, it is set in the ClientContext6::hosts_.
ctx | Client context that contains all necessary information. |
Definition at line 340 of file alloc_engine.cc.
References isc::dhcp::AllocEngine::ClientContext6::early_global_reservations_lookup_, findGlobalReservation(), isc::dhcp::AllocEngine::ClientContext6::host_identifiers_, isc::dhcp::AllocEngine::ClientContext6::hosts_, isc::dhcp::HostMgr::instance(), isc::dhcp::AllocEngine::ClientContext6::query_, and isc::dhcp::AllocEngine::ClientContext6::subnet_.
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Determines the preferred and valid v6 lease lifetimes.
A candidate triplet for both preferred and valid lifetimes will be selected from the first class matched to the query which defines the value or from the subnet if none do. Classes are searched in the order they are assigned to the query.
If the client requested a lifetime IA hint, then the lifetime values returned will be the requested values bounded by the candidate triplets. If the client did not request a value, then it simply returns the candidate triplet's default value.
ctx | client context that passes all necessary information. See ClientContext6 for details. | |
[out] | preferred | set to the preferred lifetime that should be used. |
[out] | valid | set to the valid lifetime that should be used. |
Definition at line 1878 of file alloc_engine.cc.
References isc::dhcp::ALLOC_ENGINE_DBG_TRACE, isc::dhcp::alloc_engine_logger, isc::dhcp::ALLOC_ENGINE_V6_CALCULATED_PREFERRED_LIFETIME, isc::dhcp::AllocEngine::ClientContext6::currentIA(), isc::dhcp::AllocEngine::ClientContext6::IAContext::hints_, isc::dhcp::CfgMgr::instance(), LOG_DEBUG, isc::dhcp::AllocEngine::ClientContext6::query_, and isc::dhcp::AllocEngine::ClientContext6::subnet_.
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Returns the offer lifetime based on the v4 context.
If the client query is a BOOTP query or something other than DHCPDISCOVER, return 0.
Otherwise, the value will be selected from the first class matched to the query which defines it or from the subnet if none do. Classes are searched in the order they are assigned to the query.
ctx | Client context holding various information about the client. |
Definition at line 4174 of file alloc_engine.cc.
References isc::dhcp::AllocEngine::ClientContext4::fake_allocation_, isc::dhcp::CfgMgr::instance(), isc::dhcp::AllocEngine::ClientContext4::query_, and isc::dhcp::AllocEngine::ClientContext4::subnet_.
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Get the read-write mutex.
This read-write mutex is used to make reclamation exclusive of multi-threaded packet processing.
Definition at line 1853 of file alloc_engine.h.
References rw_mutex_.
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Returns the valid lifetime based on the v4 context.
If the client query is a BOOTP query, the value returned will be Lease::INFINITY_LFT.
Otherwise, a candidate triplet will be selected from the first class matched to the query which defines it or from the subnet if none do. Classes are searched in the order they are assigned to the query.
If the client requested a lifetime value via DHCP option 51, then the lifetime value returned will be the requested value bounded by the candidate triplet. If the client did not request a value, then it simply returns the candidate triplet's default value.
ctx | Client context holding various information about the client. |
Definition at line 4209 of file alloc_engine.cc.
References isc::dhcp::DHO_DHCP_LEASE_TIME, isc::dhcp::Lease::INFINITY_LFT, isc::dhcp::CfgMgr::instance(), isc::dhcp::AllocEngine::ClientContext4::query_, and isc::dhcp::AllocEngine::ClientContext4::subnet_.
Referenced by isc::dhcp::Dhcpv4Srv::assignLease().
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Generates a label for subnet or shared-network from subnet.
Creates a string for the subnet and its ID for stand alone subnets or the shared-network and its name if the given subnet belongs to a shared-network.
subnet | pointer to the source subnet |
Definition at line 3308 of file alloc_engine.cc.
Creates an IPv6Resrv instance from a Lease6.
lease | Reference to the Lease6 |
Definition at line 788 of file alloc_engine.h.
References isc::dhcp::IPv6Resrv::TYPE_NA, isc::dhcp::Lease::TYPE_NA, and isc::dhcp::IPv6Resrv::TYPE_PD.
void isc::dhcp::AllocEngine::reclaimExpiredLeases4 | ( | const size_t | max_leases, |
const uint16_t | timeout, | ||
const bool | remove_lease, | ||
const uint16_t | max_unwarned_cycles = 0 ) |
Reclaims expired IPv4 leases.
This method retrieves a collection of expired leases and reclaims them. See https://gitlab.isc.org/isc-projects/kea/wikis/designs/lease-expiration#leases-reclamation-routine for the details.
This method is executed periodically to act upon expired leases. This includes for each lease:
Note: declined leases fall under the same expiration/reclamation processing as normal leases. In principle, it would be more elegant to have a separate processing for declined leases reclamation. However, due to performance reasons we decided to use them together. Several aspects were taken into consideration. First, normal leases are expected to expire frequently, so in a typical deployment this method will have some leases to process. Second, declined leases are expected to be very rare event, so in most cases there won't be any declined expired leases. Third, the calls to LeaseMgr to obtain all leases of specific expiration criteria are expensive, so it is better to have one call rather than two, especially if one of those calls is expected to usually return no leases.
It doesn't make sense to retain declined leases that are reclaimed, because those leases don't contain any useful information (all client identifying information was stripped when the leave was moved to the declined state). Therefore remove_leases parameter is ignored for declined leases. They are always removed.
Also, for declined leases reclaimDeclinedLease4 is called. It conducts several declined specific operation (extra log entry, stats dump, hooks).
max_leases | Maximum number of leases to be reclaimed. |
timeout | Maximum amount of time that the reclamation routine may be processing expired leases, expressed in milliseconds. |
remove_lease | A boolean value indicating if the lease should be removed when it is reclaimed (if true) or it should be left in the database in the "expired-reclaimed" state (if false). |
max_unwarned_cycles | A number of consecutive processing cycles of expired leases, after which the system issues a warning if there are still expired leases in the database. If this value is 0, the warning is never issued. |
Definition at line 2680 of file alloc_engine.cc.
References isc::dhcp::ALLOC_ENGINE_DBG_TRACE, isc::dhcp::alloc_engine_logger, isc::dhcp::ALLOC_ENGINE_V4_LEASES_RECLAMATION_FAILED, isc::dhcp::ALLOC_ENGINE_V4_LEASES_RECLAMATION_START, LOG_DEBUG, LOG_ERROR, and reclaimExpiredLeases4Internal().
void isc::dhcp::AllocEngine::reclaimExpiredLeases4Internal | ( | const size_t | max_leases, |
const uint16_t | timeout, | ||
const bool | remove_lease, | ||
const uint16_t | max_unwarned_cycles = 0 ) |
Body of reclaimExpiredLeases4.
max_leases | Maximum number of leases to be reclaimed. |
timeout | Maximum amount of time that the reclamation routine may be processing expired leases, expressed in milliseconds. |
remove_lease | A boolean value indicating if the lease should be removed when it is reclaimed (if true) or it should be left in the database in the "expired-reclaimed" state (if false). |
max_unwarned_cycles | A number of consecutive processing cycles of expired leases, after which the system issues a warning if there are still expired leases in the database. If this value is 0, the warning is never issued. |
Definition at line 2701 of file alloc_engine.cc.
References isc::dhcp::ALLOC_ENGINE_DBG_TRACE, isc::dhcp::alloc_engine_logger, isc::dhcp::ALLOC_ENGINE_V4_LEASE_RECLAMATION_FAILED, isc::dhcp::ALLOC_ENGINE_V4_LEASES_RECLAMATION_COMPLETE, isc::dhcp::ALLOC_ENGINE_V4_LEASES_RECLAMATION_SLOW, isc::dhcp::ALLOC_ENGINE_V4_LEASES_RECLAMATION_TIMEOUT, isc::dhcp::ALLOC_ENGINE_V4_NO_MORE_EXPIRED_LEASES, isc::hooks::HooksManager::calloutsPresent(), isc::hooks::HooksManager::createCalloutHandle(), Hooks, isc::dhcp::LeaseMgrFactory::instance(), isc::util::MultiThreadingMgr::instance(), LOG_DEBUG, LOG_ERROR, LOG_WARN, and rw_mutex_.
Referenced by reclaimExpiredLeases4().
void isc::dhcp::AllocEngine::reclaimExpiredLeases6 | ( | const size_t | max_leases, |
const uint16_t | timeout, | ||
const bool | remove_lease, | ||
const uint16_t | max_unwarned_cycles = 0 ) |
Reclaims expired IPv6 leases.
This method retrieves a collection of expired leases and reclaims them. See https://gitlab.isc.org/isc-projects/kea/wikis/designs/lease-expiration#leases-reclamation-routine for the details.
This method is executed periodically to act upon expired leases. This includes for each lease:
Note: declined leases fall under the same expiration/reclamation processing as normal leases. In principle, it would be more elegant to have a separate processing for declined leases reclamation. However, due to performance reasons we decided to use them together. Several aspects were taken into consideration. First, normal leases are expected to expire frequently, so in a typical deployment this method will have some leases to process. Second, declined leases are expected to be very rare event, so in most cases there won't be any declined expired leases. Third, the calls to LeaseMgr to obtain all leases of specific expiration criteria are expensive, so it is better to have one call rather than two, especially if one of those calls is expected to usually return no leases.
It doesn't make sense to retain declined leases that are reclaimed, because those leases don't contain any useful information (all client identifying information was stripped when the leave was moved to the declined state). Therefore remove_leases parameter is ignored for declined leases. They are always removed.
Also, for declined leases reclaimDeclinedLease6 is called. It conducts several declined specific operation (extra log entry, stats dump, hooks).
max_leases | Maximum number of leases to be reclaimed. |
timeout | Maximum amount of time that the reclamation routine may be processing expired leases, expressed in milliseconds. |
remove_lease | A boolean value indicating if the lease should be removed when it is reclaimed (if true) or it should be left in the database in the "expired-reclaimed" state (if false). |
max_unwarned_cycles | A number of consecutive processing cycles of expired leases, after which the system issues a warning if there are still expired leases in the database. If this value is 0, the warning is never issued. |
Definition at line 2517 of file alloc_engine.cc.
References isc::dhcp::ALLOC_ENGINE_DBG_TRACE, isc::dhcp::alloc_engine_logger, isc::dhcp::ALLOC_ENGINE_V6_LEASES_RECLAMATION_FAILED, isc::dhcp::ALLOC_ENGINE_V6_LEASES_RECLAMATION_START, LOG_DEBUG, LOG_ERROR, and reclaimExpiredLeases6Internal().
void isc::dhcp::AllocEngine::reclaimExpiredLeases6Internal | ( | const size_t | max_leases, |
const uint16_t | timeout, | ||
const bool | remove_lease, | ||
const uint16_t | max_unwarned_cycles = 0 ) |
Body of reclaimExpiredLeases6.
max_leases | Maximum number of leases to be reclaimed. |
timeout | Maximum amount of time that the reclamation routine may be processing expired leases, expressed in milliseconds. |
remove_lease | A boolean value indicating if the lease should be removed when it is reclaimed (if true) or it should be left in the database in the "expired-reclaimed" state (if false). |
max_unwarned_cycles | A number of consecutive processing cycles of expired leases, after which the system issues a warning if there are still expired leases in the database. If this value is 0, the warning is never issued. |
Definition at line 2538 of file alloc_engine.cc.
References isc::dhcp::ALLOC_ENGINE_DBG_TRACE, isc::dhcp::alloc_engine_logger, isc::dhcp::ALLOC_ENGINE_V6_LEASE_RECLAMATION_FAILED, isc::dhcp::ALLOC_ENGINE_V6_LEASES_RECLAMATION_COMPLETE, isc::dhcp::ALLOC_ENGINE_V6_LEASES_RECLAMATION_SLOW, isc::dhcp::ALLOC_ENGINE_V6_LEASES_RECLAMATION_TIMEOUT, isc::dhcp::ALLOC_ENGINE_V6_NO_MORE_EXPIRED_LEASES, isc::hooks::HooksManager::calloutsPresent(), isc::hooks::HooksManager::createCalloutHandle(), Hooks, isc::dhcp::LeaseMgrFactory::instance(), isc::util::MultiThreadingMgr::instance(), LOG_DEBUG, LOG_ERROR, LOG_WARN, and rw_mutex_.
Referenced by reclaimExpiredLeases6().
Lease6Collection isc::dhcp::AllocEngine::renewLeases6 | ( | ClientContext6 & | ctx | ) |
Renews existing DHCPv6 leases for a given IA.
This method updates the leases associated with a specified IA container. It will extend the leases under normal circumstances, but sometimes there may be reasons why not to do so. Such a reasons may be:
This method will call the lease6_renew callout.
ctx | Message processing context. It holds various information extracted from the client's message and required to allocate a lease. In particular, ClientContext6::IAContext::hints_ provides list of addresses or prefixes the client had sent. ClientContext6::IAContext::old_leases_ will contain removed leases in this case. |
Definition at line 2085 of file alloc_engine.cc.
References isc::dhcp::AllocEngine::ClientContext6::addAllocatedResource(), isc::dhcp::ALLOC_ENGINE_DBG_TRACE, isc::dhcp::ALLOC_ENGINE_DBG_TRACE_DETAIL, isc::dhcp::alloc_engine_logger, isc::dhcp::ALLOC_ENGINE_V6_EXTEND_ALLOC_UNRESERVED, isc::dhcp::ALLOC_ENGINE_V6_EXTEND_ERROR, isc::dhcp::ALLOC_ENGINE_V6_EXTEND_LEASE, isc::dhcp::ALLOC_ENGINE_V6_RENEW_HR, isc::dhcp::ALLOC_ENGINE_V6_RENEW_REMOVE_RESERVED, isc::dhcp::AllocEngine::ClientContext6::currentIA(), isc::dhcp::AllocEngine::ClientContext6::duid_, isc::dhcp::AllocEngine::ClientContext6::hosts_, isc::dhcp::AllocEngine::ClientContext6::IAContext::iaid_, isc::dhcp::LeaseMgrFactory::instance(), isc_throw, isc::dhcp::AllocEngine::ClientContext6::IAContext::isNewResource(), LOG_DEBUG, LOG_ERROR, isc::dhcp::AllocEngine::ClientContext6::new_leases_, isc::dhcp::AllocEngine::ClientContext6::query_, isc::dhcp::AllocEngine::ClientContext6::subnet_, and isc::dhcp::AllocEngine::ClientContext6::IAContext::type_.
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protected |
Stores additional client query parameters on a V4 lease.
Extended features such as LeaseQuery require additional parameters to be stored for each lease, than we would otherwise retain. This function adds that information to the lease's user-context. (Note it is protected to facilitate unit testing).
ctx
is valid. The caller is responsible for making sure that they are valid.[out] | lease | A pointer to the lease to be updated. |
ctx | A context containing information from the server about the client and its message. |
Definition at line 4969 of file alloc_engine.cc.
References isc::data::Element::boolean, isc::data::copy(), isc::data::Element::create(), isc::data::Element::createMap(), isc::dhcp::DHO_DHCP_AGENT_OPTIONS, isc::util::encode::encodeHex(), isc::dhcp::CfgMgr::instance(), isc::data::Element::map, isc::dhcp::AllocEngine::ClientContext4::query_, isc::dhcp::RAI_OPTION_RELAY_ID, isc::dhcp::RAI_OPTION_REMOTE_ID, isc::dhcp::CfgGlobals::STASH_AGENT_OPTIONS, and isc::dhcp::AllocEngine::ClientContext4::subnet_.
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protected |
Stores additional client query parameters on a V6 lease.
Extended features such as LeaseQuery and Reconfigure require additional parameters to be stored for each lease, than we would otherwise retain. This function adds that information to the lease's user-context. (Note it is protected to facilitate unit testing).
ctx
is valid. The caller is responsible for making sure that they are valid.[out] | lease | A pointer to the lease to be updated. |
ctx | A context containing information from the server about the client and its message. |
Definition at line 5053 of file alloc_engine.cc.
References isc::dhcp::Lease6::ACTION_IGNORE, isc::dhcp::Lease6::ACTION_UPDATE, isc::data::copy(), isc::data::Element::create(), isc::data::Element::createList(), isc::data::Element::createMap(), D6O_RELAY_ID, D6O_REMOTE_ID, isc::util::encode::encodeHex(), isc::data::Element::map, isc::dhcp::LibDHCP::packOptions6(), isc::dhcp::AllocEngine::ClientContext6::query_, and isc::dhcp::AllocEngine::ClientContext6::subnet_.
isc::util::ReadWriteMutex isc::dhcp::AllocEngine::rw_mutex_ |
The read-write mutex.
Definition at line 1858 of file alloc_engine.h.
Referenced by getReadWriteMutex(), reclaimExpiredLeases4Internal(), and reclaimExpiredLeases6Internal().