A new design for Kamailio's LCR module making it simpler, more powerful, and easier to manage via an admin interface.
Current LCR module lacks some useful features and it's hard to manage via an admin interface due to the complexity and not good relationship between its DB tables.
Some of the current design issues are:
Some desired features would be:
In order to simplify implementation and use, gateway groups are no longer supported. Instead, gateways are directly specified as rule targets, where each rule target has a priority and weight.
| Column | Description | Possible values | Default value |
|---|---|---|---|
| id | Primary key: identifier of this rule | Integer | |
| lcr_id | Identifier of LCR instance | Integer | |
| prefix | Prefix of Request URI user part | NULL / String | NULL |
| from_uri | Regular expression to match the From URI (or given pseudo-variable) | NULL / String (regular expression) | NULL |
| stopper | If it's 1 no other rules would be inspected after finding this one | Integer (1=on / 0=off) | 0 |
| enabled | Is it this rule active so it can be loaded? | Integer (1=on / 0=off) | 1 |
Keys:
| Column | Description | Possible values | Default value |
|---|---|---|---|
| id | Primary key | Integer | |
| rule_id | Integer pointing to the id of an entry in lcr_rule table | Integer | |
| gw_id | Gateway for this rule target (points to id in lcr_gw table) | Integer | |
| priority | Priority of this rule target within all targets for the same rule | Integer (0-255) | |
| weight | Weight of this rule target within all equal priority targets for the same rule | Integer (1-254) |
Keys:
| Column | Description | Possible values | Default value |
|---|---|---|---|
| id | Primary key, identifier of the gateway | Integer | |
| lcr_id | Identifier of LCR instance | Integer | |
| gw_name | Name of the gateway (only for documentation) | String | NULL |
| ip_addr | IP of the gateway | NULL / String | NULL |
| port | Port of the gateway | NULL (no port is added) / Integer (5060=sip / 5061=sips) | NULL |
| uri_scheme | Scheme of the Request URI | NULL / Integer (NULL and 1 = sip / 2=sips) | NULL |
| transport | Transport used for this gateway | NULL (no transport is added) / Integer (0=udp / 1=tcp / 2=tls / 3=sctp) | NULL |
| params | URI params to be added to Request URI | NULL / String | NULL |
| hostname | Hostname to set in Request URI host part | NULL / String | NULL |
| strip | Number of characters to be stripped from the front of Request URI user | NULL / Integer | NULL |
| tag | Prefix to be added to Request URI user part after removing strip characters | NULL / String | NULL |
| flags | Flags enabled when loading this gateway | Integer | 0 |
| defunct | Gateway is defunct until this Linux timestamp time | NULL (= 0) / Integer | NULL |
Keys:
When calling next_gw() function the value of flag(DONT_STRIP_OR_TAG) is inspected. If it is set then strip and tag values of the selected gateway are ignored so the Request URI user part is not modified.
This is an optional module parameter. If it's not defined then strip and tag are always applied for each gateway.
An use case in which this flag is useful:
The following configuration would do the job:
# This route ensures that the dialed number is in the form +XXXXXX # (international E164) or national (XXXXXXX without + or 00): route(NORMALIZE_NUMBER); # Load gateways as usual. load_gws(...); # If the dialed number is national then enable the flag(DONT_USE_STRIP_TAG) # to avoid the RURI user part being striped and tagged with gw values. if !(starts_with("$rU", "+")) setflag(DONT_STRIP_OR_TAG); next_gw();