Backup / Failover Routing

Backup / Failover Routing SearchSearch
Author Message
Des - NowSMS Support
Board Administrator
Username: Desosms

Post Number: 5868
Registered: 08-2008
Posted on Friday, September 22, 2017 - 06:33 pm:   

I was answering a customer e-mail question about backup routes (failover routing), and realized that we did not have a good existing explanation to reference.

By default, when there are multiple SMSC connections, NowSMS will use all connections, and distribute the messages across them.

However, there may be situations where a backup route should be used if a primary route is down.

And there is a related scenario where a First Delivery Attempt SMSC is deployed. If an error occurs when submitting to this SMSC, the message should be tried on a different SMSC connection.

Backup Routes

To configure a backup route, where the backup route is only active when another route is down, define the backup SMSC connection to NowSMS as normal, then manually edit the SMSGW.INI file. Under the SMSC section header (e.g., [Modem - driver name] or [SMPP - server:port]), add BackupForRoute=xxxxxx where xxxxxx is either the name of another SMSC connection or a "RouteName=" setting defined for one or more SMSC connections. If xxxxxx is the name of another SMSC connection, this SMSC connection will only be activated if that other SMSC connection is down. If xxxxxx is a "RouteName=" setting defined for one or more SMSC connections, this SMSC connection will only be activated if all other SMSC connections with this route name are down.

If the backup route should always be active, use BackupForRouteLive=xxxx instead of BackupForRoute. If route/connection xxxx is down, this route adds that workload to its own.

Example SMSGW.INI:
[SMPP - a.a.a.a:bbb]  
RouteName=RouteA
:
:
:
[SMPP - c.c.c.c:ddd]
RouteName=RouteB
BackupForRoute=RouteA
:
:
:


First Delivery Attempt / ReRoute on Error

If a message fails or is rejected by an SMSC connection, the ReRouteOnError setting can be used to indicated that failed messages should be rerouted to a different connection. To enable this setting, under the SMSC specific section header of SMSGW.INI (e.g., [SMPP - server:port] or [Modem - modem driver name]), add ReRouteOnError=xxxxxx, where xxxxxx is the route name for a different SMSC connection.

Note that the message will not be rerouted until the maximum retry attempts have been exceeded on the first connection. Set RetryMaxAttempts=## under the SMSC section header to indicate how many attempts are allowed before the messages is rerouted to another SMSC.

Example SMSGW.INI:
[SMPP - a.a.a.a:bbb]  
RouteName=RouteA
RetryMaxAttempts=1
ReRouteOnError=RouteB
:
:
:
[SMPP - c.c.c.c:ddd]
RouteName=RouteB
:
:
: