System Administration Guide: Network Services

Changing Default Timeouts

High network latency can cause UAs and SAs to time out before a response returns for requests and registrations. Latency can be a problem if a UA is separated from an SA, or if both a UA and an SA are separated from a DA;either by multiple subnets, a dial-up line, or a WAN. You can determine if latency is a problem by checking whether SLP requests are failing because of timeouts on UA and SA requests and registrations. You can also use the ping command to measure the actual latency.

The following table lists configuration properties that control timeouts. You can use the procedures in this section to modify these properties.

Table 9–4 Time-out Properties


Property	Description
`net.slp.multicastTimeouts` `net.slp.DADiscoveryTimeouts` `net.slp.datagramTimeouts`	The properties that control timeouts for repeated multicast and unicast UDP message transmissions before the transmission is abandoned.
`net.slp.multicastMaximumWait`	The property that controls the maximum amount of time a multicast message is transmitted before it is abandoned.
`net.slp.datagramTimeouts`	The upper bound of a DA timeout that is specified by the sum of values that are listed for this property. A UDP datagram is repeatedly sent to a DA until a response is received or the time-out bound is reached.

If frequent timeouts are occurring during multicast service discovery or DA discovery, increase the net.slp.multicastMaximumWait property from the default value of 15000 milliseconds (15 seconds). Increasing the maximum wait period allows more time for requests on high latency networks to be completed. After you change the net.slp.multicastMaximumWait, you should also modify the net.slp.multicastTimeouts and net.slp.DADiscoveryTimeouts. The sum of the timeout values for these properties equals the net.slp.multicastMaximumWait value.