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When you create WAN connections, you can establish the following outbound call attributes for permanent and on-demand calls:
This topic contains the following sections:
By default, a PPP WAN connection retries all self-correcting failures at increasing intervals until the call is established, with a retry interval limit of 10 minutes for permanent connections and 2 minutes for on-demand connections.
You can use the Retry Mode parameter to specify the conditions under which a failed permanent connection is retried automatically. Its default setting, Retry Self-Correcting Failures , uses error information from NetWare Link/PPP to differentiate between errors that are self-correcting, such as a busy telephone number, and errors that require user intervention, such as a call authentication failure.
Alternatively, you can set up your system to retry all failures (Retry All ) or to never retry at all (Never Retry ). Retrying all failures is used for unattended environments and for situations in which configuration changes are not easily made to the router. For example, it might be easier to correct problems at the peer system or WAN service provider system, and simply let the router continue to retry until the problem is corrected. However, this is not advisable when a cost is associated with each connection attempt.
Retrying failed connections results in successive connection attempts with an increasing delay between each attempt. By default, the delay is set initially to 1 second, and it is increased exponentially until the maximum delay specified by the Retry Interval Limit parameter is reached.
WARNING: Some retry intervals might be slightly longer than expected because NetWare Link/PPP employs a random backoff interval to decrease the chance of collisions between calling systems.
The Retry Limit Handling parameter defines connection attempt behavior after the retry interval limit has been reached. Retries can continue indefinitely at the configured interval limit, or retry attempts can be terminated and the connection failed. For permanent connections, keep the default, Continuous At Limit , to support unattended operation. Otherwise, use Stop At Limit if a cost is associated with each connection attempt.
For on-demand connections, the default is Stop At Limit .
You can specify the amount of time that an on-demand connection remains active without the presence of data by setting the Idle Connection Timeout WAN call destination parameter. The default timeout of 10 minutes is usually a reasonable compromise between performance and cost effectiveness when using public-switched telephone networks.
WARNING: Setting this value too low can cause the connection to terminate before data is actually sent. This forces multiple-connection establishment and degradation of data transfer performance.
Consider switched-circuit connection billing policies when modifying the value of the timeout. If a large percentage of the connection cost is based on the call duration, reduce the value to minimize costs. If a large percentage of the connection cost is based on establishing the initial connection, and if the call duration is less of a factor, increase the value.
To configure WAN call retry and timeout parameters, complete the following steps:
Load NIASCFG, then select the following parameter path:
Select Configure NIAS > Protocols and Routing > WAN Call Directory
Scroll to the WAN call you are configuring, then select it.
The PPP Call Destination Configuration menu is displayed.
To set the idle connection timeout, do the following:
Select Call Retry Options and do one or more of the following:
To set the retry mode, do the following:
To set retry limit handling, do the following:
To set the retry interval limit, do the following:
Press Esc to return to the Internetworking Configuration menu; save your changes when prompted.
If you want these changes to take effect immediately, select Reinitialize System .
If you want to configure other parameters, do so now, then reinitialize the system when you are finished.
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