October 10, 2006 — Tactical Software today announced the release of version 4.8 of its product line, which adds automatic failover support in the DialOut/EZ and Serial/IP COM Port Redirectors. This industry first enables the use of multiple device servers, avoiding potential single points of failure. This new feature is especially useful with dial-out modem pools.
In version 4.8, both DialOut/EZ and Serial/IP COM Port Redirectors allow multiple device servers (modem pools or serial servers) to be specified for each virtual COM port. If the redirector is unable to establish a connection to a server, it automatically attempts to reach the next server, in the order specified.
Automatic failover makes it easy to configure backup modem servers that will be immediately used if a primary server is unavailable. Failover also allows multiple modem servers to be used as one large pool of modems that is tolerant of failures of individual modem servers.
Tactical's automatic failover is compatible with most TCP/IP dial-out modem pools and serial servers, with no special server software configuration required. Compatible servers include PC-based servers running the Tactical Software TacServe COM Port Server software, which includes the DialOut/EZ or Serial/IP COM Port Redirector.
To provide more control of connection attempts and failure determination, a new option in Tactical Software redirectors can be used to enforce a maximum duration of each attempt to connect to a server. This option allows applications to avoid the unpredictable failure times determined by the Windows TCP/IP stack and permits quick sequencing through modem servers to preserve connection timing requirements of applications.
Also in version 4.8, the DialOut/EZ Site Edition Redirector supports failover to backup servers running the Tactical Software License Manager, eliminating the licensing mechanism as a potential single point of failure for customers using Tactical's site licensing.
