Add listen threads

When you start the database server, the oninit process starts a listen thread for servers with the server names and server alias names that you specify with the DBSERVERNAME and DBSERVERALIASES configuration parameters. You can add listen threads for additional ports.

You can also set up multiple listen threads for one service (port) for the onimcsoc or onsoctcp protocol.

To add listen threads for additional ports, you must first use the DBSERVERALIASES parameter to specify dbservernames for each of the ports. For example, the DBSERVERALIASES parameter in the following figure defines two additional dbservernames, soc_ol2 and soc_ol3, for the database server instance identified as soc_ol1.

DBSERVERNAME      soc_ol1
DBSERVERALIASES   soc_ol2,soc_ol3

After you define additional dbservernames for the database server, you must specify an interface/protocol combination and port for each of them in the sqlhosts file or registry. Each port is identified by a unique combination of hostname and servicename entries. For example, the sqlhosts entries shown in the following table cause the database server to start three listen threads for the onsoctcp interface/protocol combination, one for each of the ports defined.

Table 1. The sqlhosts entries to listen to multiple ports for a single interface/protocol combination
dbservername	nettype	hostname	service name
soc_ol1	onsoctcp	myhost	port1
soc_ol2	onsoctcp	myhost	port2
soc_ol3	onsoctcp	myhost	port3

If you include a NETTYPE parameter for an interface/protocol combination, it applies to all the connections for that interface/protocol combination. In other words, if a NETTYPE parameter exists for onsoctcp in the previous table, it applies to all of the connections shown. In this example, the database server runs one poll thread for the onsoctcp interface/protocol combination unless the NETTYPE parameter specifies more. For more information about entries in the sqlhosts file or registry, see Connectivity files.

Setting up multiple listen threads for one port for the onimcsoc or onsoctcp protocol

To set up multiple listen threads for one service (port) for the onimcsoc or onsoctcp protocol, specify DBSERVERNAME and DBSERVERALIASES information as follows:

DBSERVERNAME <name>-<n>
DBSERVERALIASES <name1>-<n>,<name2>

For example:

To bring up two listen threads for the server with the DBSERVERNAME of ifx, specify:
```
DBSERVERNAME ifx-2
```
To bring up two listen threads for DBSERVERALIASES ifx_a and ifx_b, specify:
```
DBSERVERALIASES ifx_a-2,ifx_b-2
```