Thanks Juha
I populated the lcr tables by hand. This is how they look now, I have 2 lcr_ids [1 and 2], each instance has its own gw. And each instance has its own prefix to match for [4444 and 5555].
The idea is that a call comes in with R-URI 444413051234567, it should match the lcr_id= 200, then it should go out using gw 192.168.169.200 etc

mysql> select * from lcr_gw;
+----+--------+------------+-----------------+-------------------+------+--------+------------+-----------+-------+------+-------+---------+
| id | lcr_id | gw_name    | ip_addr         | hostname          | port | params | uri_scheme | transport | strip | tag  | flags | defunct |
+----+--------+------------+-----------------+-------------------+------+--------+------------+-----------+-------+------+-------+---------+
|  1 |    200 | switchvox  | 192.168.169.200 | pbx1.mydomain.com | 5060 | none   |          1 |         1 |     0 |      |     0 |       0 |
|  2 |    201 | switchvox2 | 192.168.169.201 | pbx1.mydomain.net | 5060 | none   |          1 |         1 |     0 |      |     0 |       0 |
+----+--------+------------+-----------------+-------------------+------+--------+------------+-----------+-------+------+-------+---------+
mysql> select * from lcr_rule;
+----+--------+--------+----------+---------+---------+
| id | lcr_id | prefix | from_uri | stopper | enabled |
+----+--------+--------+----------+---------+---------+
|  1 |    200 | 4444   |          |       0 |       1 |
|  2 |    201 | 5555   |          |       0 |       1 |
+----+--------+--------+----------+---------+---------+
mysql> select * from lcr_rule_target;
+----+--------+---------+-------+----------+--------+
| id | lcr_id | rule_id | gw_id | priority | weight |
+----+--------+---------+-------+----------+--------+
|  1 |    200 |       1 |     1 |        5 |      1 |
|  2 |    201 |       2 |     2 |        5 |      1 |
+----+--------+---------+-------+----------+--------+

Then I tried the sercmd commands to reload and dump and I do not see the contents o the screen. Is this how is supposed to work now?. How do I know that the new values are being loaded into memory w/o restarting kamailio?

I am trying to port our setup from kamailio 1.4.3 to 3.1.4 and I see
> huge differences on the LCR module.

there is a script somewhere (read wiki) that upgrades the tables.

> I have these main questions:
> 
> 1- does lcr_id replaces the grp_id?

not really.  lcr_ids denote independent lcr instances.

> 2- what happened to the fifo commands to add gws etc:

fifo commands to manipulate lcr tables are not supported by me.

-- juha