# &adminguide;

## Overview

The User location module keeps a user location table and provides access to the table for other modules. The module exports no functions that can be used directly from routing scripts.

### Contact matching

How the contacts are matched (for the same AOR - Address of Record) is an important aspect of the usrloc module, especially in the context of NAT traversal - this raises more problems since contacts from different phones of the same user may overlap (if both are behind NATs with the same configuration) or the re-register contact of the same phone may be seen as a new one (due different binding via NAT).

The SIP RFC 3261 publishes a matching algorithm based only on the contact string with Call-id and Cseq extra checking (if the Call-ID is the same, it must have a higher Cseq number, otherwise it is invalid). But as argued above, this is not enough in NAT traversal context, so the &kamailio; implementation of contact matching offers more algorithms:

- Contact based only - it is strict RFC 3261 compliancy - the Contact URI is matched as string and extra checked via Call-ID and cseq (if Call-ID is the same, it must have a higher cseq number, otherwise it is invalid).

- Contact and Call-id based - it is an extension of the first case - the contact and Call-ID must be matched as string; the cseq must be higher than the previous one - so be careful how you deal with REGISTER retransmissions in this case.

- contact and path based - it is an extension of the first case - the contact and path must be matched as string; the cseq must be higher than the previous one - so be careful how you deal with REGISTER retransmissions in this case.

- Call-id only based - it is not according to RFC3261, as it will check the Call-ID only (independent of the Contact-Header or Path).

To find out how to control/select the contact matching algorithm, please see the module parameter matching_mode - usrloc.p.matching_mode.

## Dependencies

### &kamailio; Modules

The following modules must be loaded before this module:

- Optionally a database module.

### External Libraries or Applications

The following libraries or applications must be installed before running &kamailio; with this module loaded:

- None.

## Parameters

### `nat_bflag` (int)

The index of the branch flag to be used as NAT marker (if the contact is or not natted). This is a branch flag and it will be imported and used by all other modules depending of usrloc module.

Default value is not set.

#### Set `nat_bflag` parameter

    ...
    modparam("usrloc", "nat_bflag", 3)
    ...

### `user_column` (string)

Name of database column containing usernames.

Default value is username.

#### Set `user_column` parameter

    ...
    modparam("usrloc", "user_column", "username")
    ...

### `domain_column` (string)

Name of database column containing domains.

Default value is domain.

#### Set `user_column` parameter

    ...
    modparam("usrloc", "domain_column", "domain")
    ...

### `contact_column` (string)

Name of database column containing contacts.

Default value is contact.

#### Set `contact_column` parameter

    ...
    modparam("usrloc", "contact_column", "contact")
    ...

### `expires_column` (string)

Name of database column containing expires value.

Default value is expires.

#### Set `expires_column` parameter

    ...
    modparam("usrloc", "expires_column", "expires")
    ...

### `q_column` (string)

Name of database column containing q values.

Default value is q.

#### Set `q_column` parameter

    ...
    modparam("usrloc", "q_column", "q")
    ...

### `callid_column` (string)

Name of database column containing Call-ID values.

Default value is callid.

#### Set `callid_column` parameter

    ...
    modparam("usrloc", "callid_column", "callid")
    ...

### `cseq_column` (string)

Name of database column containing Cseq.

Default value is cseq.

#### Set `cseq_column` parameter

    ...
    modparam("usrloc", "cseq_column", "cseq")
    ...

### `methods_column` (string)

Name of database column containing supported methods.

Default value is methods.

#### Set `methods_column` parameter

    ...
    modparam("usrloc", "methods_column", "methods")
    ...

### `flags_column` (string)

Name of database column to save the internal flags of the record.

Default value is flags.

#### Set `flags_column` parameter

    ...
    modparam("usrloc", "flags_column", "flags")
    ...

### `cflags_column` (string)

Name of database column to save the branch/contact flags of the record.

Default value is cflags.

#### Set `cflags_column` parameter

    ...
    modparam("usrloc", "cflags_column", "cflags")
    ...

### `user_agent_column` (string)

Name of database column containing user-agent values.

Default value is user_agent.

#### Set `user_agent_column` parameter

    ...
    modparam("usrloc", "user_agent_column", "user_agent")
    ...

### `received_column` (string)

Name of database column containing the source IP, port, and protocol from the REGISTER message.

Default value is received.

#### Set `received_column` parameter

    ...
    modparam("usrloc", "received_column", "received")
    ...

### `socket_column` (string)

Name of database column containing the received socket information (IP:port) for the REGISTER message.

Default value is socket.

#### Set `socket_column` parameter

    ...
    modparam("usrloc", "socket_column", "socket")
    ...

### `path_column` (string)

Name of database column containing the Path header.

Default value is path.

#### Set `path_column` parameter

    ...
    modparam("usrloc", "path_column", "path")
    ...

### `ruid_column` (string)

Name of database column containing the Kamailio record unique id.

Default value is ruid.

#### Set `ruid_column` parameter

    ...
    modparam("usrloc", "ruid_column", "myruid")
    ...

### `instance_column` (string)

Name of database column containing the SIP instance ID (GRUU - RFC5627). This is a unique device identifier - UUID.

Default value is instance.

#### Set `instance_column` parameter

    ...
    modparam("usrloc", "instance_column", "myinstance")
    ...

### `reg_id_column` (string)

Name of database table column containing the value for reg-id.

Default value is reg_id.

#### Set `reg_id_column` parameter

    ...
    modparam("usrloc", "reg_id_column", "r_id")
    ...

### `server_id_column` (string)

Name of database table column containing the value for server id.

Default value is server_id.

#### Set `server_id_column` parameter

    ...
    modparam("usrloc", "server_id_column", "srv_id")
    ...

### `connection_id_column` (string)

Name of database table column containing the value for connection id.

Default value is connection_id.

#### Set `connection_id_column` parameter

    ...
    modparam("usrloc", "connection_id_column", "con_id")
    ...

### `keepalive_column` (string)

Name of database table column containing the value for keepalive status.

Default value is keepalive.

#### Set `keepalive_column` parameter

    ...
    modparam("usrloc", "keepalive_column", "kalive")
    ...

### `partition_column` (string)

Name of database table column containing the value for partition id.

Default value is partition.

#### Set `partition_column` parameter

    ...
    modparam("usrloc", "partition_column", "part")
    ...

### `use_domain` (int)

If the domain part of the user should be also saved and used for identifying the user (along with the username part). Useful in multi domain scenarios. Non 0 value means true.

Default value is 0 (false).

#### Set `use_domain` parameter

    ...
    modparam("usrloc", "use_domain", 1)
    ...

### `desc_time_order` (int)

If the user's contacts should be kept timestamp ordered; otherwise the contact will be ordered based on q value. Non 0 value means true.

Default value is 0 (false).

#### Set `desc_time_order` parameter

    ...
    modparam("usrloc", "desc_time_order", 1)
    ...

### `timer_interval` (int)

Number of seconds between two timer runs. The module uses a timer to delete expired contacts, synchronize with database, send keepalives and other tasks, that need to be run periodically.

Default value is 60.

#### Set `timer_interval` parameter

    ...
    modparam("usrloc", "timer_interval", 120)
    ...

### `db_url` (string)

&url; of the database that should be used.

Default value is &defaultdb;.

#### Set `db_url` parameter

    ...
    modparam("usrloc", "db_url", "&exampledb;")
    ...

### `db_mode` (int)

The usrloc module can utilize a database for persistent contact storage. If a database is used, the location database (contacts) will survive machine restarts or software crashes. The disadvantage is that accessing a database can be very time consuming. Therefore, usrloc module implements four database accessing modes:

- 0 - This disables database completely. Only memory will be used. Contacts will not survive restart. Use this value if you need a really fast usrloc and contact persistence is not necessary or is provided by other means.

- 1 - Write-Through scheme. All changes to usrloc are immediately reflected in database too. This is very slow, but very reliable. Use this scheme if speed is not your priority but need to make sure that no registered contacts will be lost during crash or reboot.

- 2 - Write-Back scheme. This is a combination of previous two schemes. All changes are made to memory and database synchronization is done in the timer. The timer deletes all expired contacts and flushes all modified or new contacts to database. Use this scheme if you encounter high-load peaks and want them to process as fast as possible. The mode will not help at all if the load is high all the time. Also, latency of this mode is much lower than latency of mode 1, but slightly higher than latency of mode 0.

- 3 - DB-Only scheme. No memory cache is kept, all operations being directly performed with the database. The timer deletes all expired contacts from database - cleans after clients that didn't un-register or re-register. The mode is useful if you configure more servers sharing the same DB without any replication at SIP level. The mode may be slower due the high number of DB operation. For example NAT pinging is a killer since during each ping cycle all natted contact are loaded from the DB; The lack of memory caching also disable the statistics exports.

- 4 - This uses database to load records at startup but uses only memory during the runtime. Records are not written back at all, not even at shutdown. Useful for scenarios when registrations are replicated to a node that does the storage in a database during runtime.

In case of crash or restart contacts that are in memory only and haven't been flushed yet will get lost. If you want minimize the risk, use shorter timer interval.

Default value is 0.

#### Set `db_mode` parameter

    ...
    modparam("usrloc", "db_mode", 2)
    ...

### `db_load` (int)

Determine if the usrloc module should load contacts from the database storage during module initialization. A value of 0 disables the loading from the database, this parameter is ignored if db_mode 4 is set.

Default value is 1.

#### Set `db_load` parameter

    ...
    modparam("usrloc", "db_load", 0)
    ...

### `db_insert_update` (int)

Determine if the usrloc module should do an update when a duplicate key is found while inserting A value of 1 will activate update on duplicate key

Default value is 0.

#### Set `db_insert_update` parameter

    ...
    modparam("usrloc", "db_insert_update", 1)
    ...

### `matching_mode` (int)

What contact matching algorithm to be used. Refer to section contact-matching-algs for the description of the algorithms.

The parameter may take the following values:

- 0 - CONTACT ONLY based matching algorithm.

- 1 - CONTACT and CALLID based matching algorithm.

- 2 - CONTACT and PATH based matching algorithm. This mode is like mode 0 but allows for duplicate contacts from differing paths. If no path is available, it defaults to mode 0.

- 3 - CALLID only based matching algorithm. This mode will discard any duplicate registration coming through different paths.

Default value is 0 (CONTACT_ONLY).

#### Set `matching_mode` parameter

    ...
    modparam("usrloc", "matching_mode", 1)
    ...

### `cseq_delay` (int)

Delay (in seconds) for accepting as retransmissions register requests with same Call-ID and Cseq. The delay is calculated starting from the receiving time of the first register with that Call-ID and Cseq.

Retransmissions within this delay interval will be accepted and replied as the original request, but no update will be done in location. If the delay is exceeded, error is reported.

A value of 0 disable the retransmission detection.

Default value is 20 seconds.

#### Set `cseq_delay` parameter

    ...
    modparam("usrloc", "cseq_delay", 5)
    ...

### `fetch_rows` (int)

The number of the rows to be fetched at once from database when loading the location records. This value can be used to tune the load time at startup. For 1MB of private memory (default) it should be below 4000. The database driver must support fetch_result() capability.

Default value is 2000.

#### Set `fetch_rows` parameter

    ...
    modparam("usrloc", "fetch_rows", 3000)
    ...

### `hash_size` (int)

The number of entries of the hash table used by usrloc to store the location records is 2^hash_size. For hash_size=4, the number of slots of the hash table is 16.

Default value is 10 (1024 slots).

#### Set `hash_size` parameter

    ...
    modparam("usrloc", "hash_size", 12)
    ...

### `preload` (string)

Preload location table given as value. A location table is loaded based on fixup of registrar functions, therefore you need to use this parameter only to load tables that are not used by registrar module directly in configuration file.

Default value is NULL.

#### Set `preload` parameter

    ...
    modparam("usrloc", "preload", "location")
    ...

### `db_update_as_insert` (int)

Set this parameter if you want to do INSERT DB operations instead of UPDATE DB operations. It is recommended to set this parameter if you use Cassandra as a DB backend.

Default value is 0.

#### Set `db_update_as_insert` parameter

    ...
    modparam("usrloc", "db_update_as_insert", 1)
    ...

### `db_check_update` (int)

Set this parameter to 1 if you want to do DB INSERT if the number of affected rows by contact DB UPDATE operation is 0. The database module driver has to implement affected_rows() DB API function, otherwise this parameter is ignored - e.g., MySQL and Postgres DB connectors offer affected_rows().

Default value is 0 (no DB INSERT).

#### Set `db_check_update` parameter

    ...
    modparam("usrloc", "db_check_update", 1)
    ...

### `timer_procs` (int)

Number of timer processes to be started by module. Timer processes take care of checking expired records and synchronization with database. If set to 0, no dedicated timer is started, the one from core will be used.

If the number of timer processes is greater than 1, the workload of synchronization and record expiration is split up among the multiple processes. (Each process is assigned a range of slots from the internal hash table, and is responsible for cleanup and storage on those slots.)

Default value is 0.

#### Set `timer_procs` parameter

    ...
    modparam("usrloc", "timer_procs", 4)
    ...

### `xavp_contact` (string)

The name of XAVP storing the attributes per contact. They are saved in location record and restored at lookup. The tm module parameter `xavp_contact` must also be set to the same value to use the `t_load_contacts` and `t_next_contacts` functions.

Default value is NULL.

#### Set `xavp_contact` parameter

    ...
    modparam("tm|usrloc", "xavp_contact", "ulattrs")
    ...

### `db_ops_ruid` (int)

If set to 1, database queries for update or delete are done using ruid value. If it is set to 0, the old style using aor, contact and call-id is done.

Default value is 1.

#### Set `db_ops_ruid` parameter

    ...
    modparam("usrloc", "db_ops_ruid", 0)
    ...

### `handle_lost_tcp` (int)

If set to 1, Kamailio will remove location records made via TCP/TLS/WS/WSS transports when it looses corresponding tcp connections. Does not currently work in DB-Only scheme.

Default value is 0.

#### Set `handle_lost_tcp` parameter

    ...
    modparam("usrloc", "handle_lost_tcp", 1)
    ...

### `close_expired_tcp` (int)

If set to 1, Kamailio will close the TCP connection when a contact has expired, if the corresponding transport is TCP/TLS/WS/WSS.

Default value is 0.

#### Set `close_expired_tcp` parameter

    ...
    modparam("usrloc", "close_expired_tcp", 1)
    ...

### `expires_type` (int)

If set to 1, &kamailio; expects to deal with BIGINT type on database columns for expires and last modified values. It allows to handle better the daylight time adjustments. If set to 0, those columns are expected to be on default type 'DATETIME'. When it is 1, the database columns types have to be changed manually to 'BIGINT'.

Default value is 0.

#### Set `expires_type` parameter

    ...
    modparam("usrloc", "expires_type", 1)
    ...

### `db_raw_fetch_type` (int)

This affect DB-only mode and controls what kind of raw query is used to fetch the contacts from database for specific needs (e.g., sending NAT keepalives). If it is set to 0, then the common SQL query is used (working for MySQL, PostgreSQL, ...). If it is set to 1, the query required by Oracle is used.

Default value is 0.

#### Set `db_raw_fetch_type` parameter

    ...
    modparam("usrloc", "db_raw_fetch_type", 1)
    ...

### `db_insert_null` (int)

If set to 1, the insert operation to database will add null values in the statement. It has to be set to 1 for the database systems that do not have table definitions that create automatically the null fields (e.g., db_mongodb) for each stored record.

When set to 0, the fields that default to null are not added to the DB insert statement if they don't have a different value, making the query smaller.

Default value is 0 (don't add null fields in insert statement).

#### Set `db_insert_null` parameter

    ...
    modparam("usrloc", "db_insert_null", 1)
    ...

### `skip_remote_socket` (int)

If set to 1, Kamailio will skip location record when loading from database, if socket value of the record does not in kamailio listening socket list.

Default value is 0.

#### Set `skip_remote_socket` parameter

    ...
    modparam("usrloc", "skip_remote_socket", 1)
    ...

### `db_timer_clean` (int)

Enable (1) or disable (0) cleaning of expired db records on timer basis for db_mode WRITE-BACK and WRITE-THROUGH. It uses the secondary timer process.

Default value is 0.

#### Set `db_timer_clean` parameter

    ...
    modparam("usrloc", "db_timer_clean", 1)
    ...

### `rm_expired_delay` (int)

Specify the number of seconds to delay the removal of expired records. For now it works for DB_ONLY mode (db_mode=3).

Default value is 0.

#### Set `rm_expired_delay` parameter

    ...
    modparam("usrloc", "rm_expired_delay", 30)
    ...

### `server_id_filter` (int)

Enable (1) or disable (0) filter records by server_id on load and during cleaning of expired db records. It could be useful when you want to use the same location table for several kamailio instances which are configured to work in db_mode=1 or db_mode=2 (cache modes). Otherwise one instance of proxy cleans records made by another proxy and that breaks its cache.

Default value is 0.

#### Set `server_id_filter` parameter

    ...
    modparam("usrloc", "server_id_filter", 1)
    ...

### `version_table` (int)

If set to 0, the module will skip checking the version for location table.

Default value is 1 (check for table version).

#### `version_table` parameter usage

    ...
    modparam("usrloc", "version_table", 0)
    ...

### `ka_mode` (int)

Keepalive mode - control the internal keepalive mechanism. With this feature enabled, the module sends periodically (based on timer interval) SIP requests to location contacts and measures the round trip in microseconds (the round trip value can be seen in the response of the RPC command 'ul.dump').

Its value is a set of flags:

- 0 - if the value is zero, no keepalive is sent

- 1 (bit 1 set) - if set to 1, the keepalive is enabled for all contacts

- 2 (bit 2 set) - the keepalive is sent only for natted contacts (nat_bflag set)

- 4 (bit 3 set) - the keepalive is sent only for UDP contacts

For example, if set to 6, then keepalive is sent only natted UDP contacts.

Note: the internal keepalive of usrloc module conflicts in some way with the keepalive done by nathelper module. It is recommended to enable only one.

Note: the internal keepalive is for the moment implemented only for contact records stored in memory.

Note: it is recommended to set 'timer_procs' parameter in order to have dedicated timer processes for usrloc module and off-load the keepalive sending process from the core timers.

Note: Keepalives will be sent to the IP and port using the transport defined in the received column. If not set, then keepalives will be sent to the AOR using UDP as a default transport. If available, the TCP connection will be re-used for WS, TCP and TLS.

Default value is 0 (keepalive disabled).

#### `ka_mode` parameter usage

    ...
    modparam("usrloc", "ka_mode", 1)
    ...

### `ka_method` (str)

The SIP method type for keepalive requests.

Default value is OPTIONS.

#### `ka_method` parameter usage

    ...
    modparam("usrloc", "ka_method", "NOTIFY")
    ...

### `ka_from` (str)

The SIP URI to be set in the From header of the keepalive requests.

Default value is sip:server@kamailio.org.

#### `ka_from` parameter usage

    ...
    modparam("usrloc", "ka_from", "sip:server@mydomain.com")
    ...

### `ka_domain` (str)

The domain to be set in To header URI if the multi-domain is not enabled. If multi-domain is enabled, then the domain from the location record is used and this parameter is ignored.

Default value is kamailio.org.

#### `ka_domain` parameter usage

    ...
    modparam("usrloc", "ka_domain", "mydomain.com")
    ...

### `ka_filter` (int)

Set filters for keepalive processing.

Its value is a set of flags:

- 0 - if the value is zero, no filter is enabled for keepalives

- 1 (bit 1 set) - keepalives sent only to records matching the server_id global parameter.

Default value is 0 (no filter).

#### `ka_filter` parameter usage

    ...
    modparam("usrloc", "ka_filter", 1)
    ...

### `ka_timeout` (int)

The parameter sets the interval in seconds after which a contact is removed from location table if it does not reply to SIP keepalives (usually OPTIONS ping requests).

The features is available only for contacts that are stored in memory (not working for db only mode of the usrloc module).

Keepalives are sent stateless, not using TM module. The value of this parameter has to be few times higher than timer interval.

Default value is 0 (feature disabled).

#### Set `ka_timeout` parameter

    ...
    modparam("usrloc", "ka_timeout", 120)
    ...

### `ka_interval` (int)

The parameter sets the interval in seconds after which a new keepalive request should be sent for a location record.

Default value is 40.

#### Set `ka_interval` parameter

    ...
    modparam("usrloc", "ka_interval", 30)
    ...

### `ka_randomize` (int)

The parameter sets the the upper limit to the range of random seconds to be added to ka_interval before checking if a new keepalive request has to be sent. It should help to distribute better the sending of keepalive requests. The keepalive for a location record is going to be sent in a random fashion between (ka_interval + 0) and (ka_interval + ka_randomize).

Default value is 20.

#### Set `ka_randomize` parameter

    ...
    modparam("usrloc", "ka_interval", 30)
    ...

### `ka_loglevel` (int)

The level to print the log message when the keepalive response is received. It should be a value between -5 (L_ALERT) and 3 (L_DBG).

Default value is 255 (disabled).

#### `ka_loglevel` parameter usage

    ...
    modparam("usrloc", "ka_loglevel", 1)
    ...

### `ka_logmsg` (str)

The formatted log specification to be added to the message printed when the keepalive is received and roundtrip time is computed. The log message starts with "keepalive roundtrip: %u.%06u sec - ruid [%.*s]", then concatenates the value of this parameter and the end of line.

The value of this parameter can contain script variables that are evaluated with the SIP response.

Default value is to-uri: [$tu] remote-addr: [$sas].

#### `ka_logmsg` parameter usage

    ...
    modparam("usrloc", "ka_logmsg", " to-uri: [$tu] remote-addr: [$sas]")
    ...

### `ka_reply_codes` (str)

Comma separated list of reply code values or reply code classes to be considered valid for keepalive processing. If the reply code does not match any of them, then the reply is ignored, not considered a valid response to keepalive request. It could be useful to skip replies from intermediary proxies that could not forward the request.

Default value is 0 (checking of reply code is not done, are responses are considered valid).

#### `ka_reply_codes` parameter usage

    ...
    modparam("usrloc", "ka_reply_codes", "2,405,486")
    ...

### `load_rank` (int)

Allows to set the rank of the child SIP worker to load the location records.

Default value is 1 (PROC_SIPINIT).

#### `load_rank` parameter usage

    ...
    modparam("usrloc", "load_rank", 1)
    ...

### `db_clean_tcp` (int)

If set to 1, when &kamailio; starts it removes the contacts with transport TCP, TLS or WSS, no longer loading them. Useful when end points do not listen for incoming connections on contact address, which is quite common (end point use only tcp client connections). On restart, connections are lost, therefore the corresponding contact records become useless.

Default value is 0 (do not clean tcp contacts).

#### `db_clean_tcp` parameter usage

    ...
    modparam("usrloc", "db_clean_tcp", 1)
    ...

## RPC Commands

### `ul.dump`

Dumps the content of the location table

Parameters:

- None.

### `ul.lookup table AOR`

Looks up the contents of an AOR entry in the location table

Parameters:

- table name - table where the AOR resides (Ex: location).

- AOR - user AOR in username[@domain] format (domain must be supplied only if use_domain option is on).

### `ul.rm table AOR`

Deletes an entire AOR record (including its contacts).

Parameters:

- table name - table where the AOR resides (Ex: location).

- AOR - user AOR in username[@domain] format (domain must be supplied only if use_domain option is on).

### `ul.rm_contact table AOR contact`

Deletes a contact from an AOR record.

Parameters:

- table name - table where the AOR is removed from (Ex: location).

- AOR - user AOR in username[@domain] format (domain must be supplied only if use_domain option is on).

- contact - exact contact to be removed

### `ul.flush`

Triggers the flush of USRLOC memory cache into DB from the RPC process. It succeeds only if the the db_mode is set to a value that enables connectivity to database.

### `ul.add`

Adds a new contact for a user AOR.

Parameters:

- table name - table where the contact will be added (Ex: location).

- AOR - user AOR in username[@domain] format (domain must be supplied only if use_domain option is on).

- contact - contact string to be added

- expires - expires value of the contact

- Q - Q value of the contact

- path value with the Path vector (use '0' or '.' if it should not be set)

- flags - internal USRLOC flags of the contact

- cflags - per branch flags of the contact

- methods - mask with supported requests of the contact

- received (optional) value with the received-from address (source address) (use '0' or '.' if it should not be set). Format: sip:srcip:srcport;transport=abc

- socket (optional) value with the local socket address (use '0' or '.' if it should not be set). Format: proto:localip:localport

Note: the position of parameters is relevant, in the case of optional parameters, use '0' or '.' for parameters that should not be set which are positioned before any parameter that has to be set.

### `ul.db_users`

Tell number of different users (AoRs) in a location table that have unexpired contacts.

Parameters:

- table name - location table where the users are looked for, for example, location.

### `ul.db_contacts`

Tell number of unexpired contacts in a location table.

Parameters:

- table name - location table where the contacts are looked for, for example, location.

### `ul.db_expired_contacts`

Tell number of expired contacts in a location table.

Parameters:

- table name - location table where the contacts are looked for, for example, location.

## Statistics

Exported statistics are listed in the next sections.

### users

Number of AOR existing in the USRLOC memory cache for that domain - can not be reset; this statistic will be registered for each used domain (Ex: location).

### contacts

Number of contacts existing in the USRLOC memory cache for that domain - can not be reset; this statistic will be registered for each used domain (Ex: location).

### expires

Total number of expired contacts for that domain - can be reset; this statistic will be registered for each used domain (Ex: location).

### registered_users

Total number of AOR existing in the USRLOC memory cache for all domains - can not be reset.