Failover switches

Failover switches (also called Fallback, Line Protection, or A/B Fallback switches) can switch a circuit between two based on a manual or automatic trigger. Some can be controlled via TCP/IP.

• POTS line failover
• Grandstream HA100 High Availability Controller
  • • Digium R-Series R800 Digium are the people who make Asterisk, and the Digium R800 provides 8 POTS ports that can be automatically transferred to different endpoints (This product is completely supported by FreePBX HA)
  • beroNet Failover Switch 4 Port Failoverswitch. Supporting PRI/BRI/FXS/FXO/Ethernet. 2 Modes (Failover and Fallback)
  • Use a line splitter and hope Asterisk does not fail off-hook
  • Use a line splitter that gives priority to one line (the backup line)
  • Viking Electronics makes a failover device for up to 6 lines: PF-6
  • DataProbe switches (some controllable via TCP/IP)
  • the Sipura SPA 3000 has one fxo and one fxs port. If the power goes out it will automatically connect the two ports
  • beroNet berofos Multiport Failover Switch 4 Port PRI/BRI/Analog/Ethernet Failover Switch controllable via Network
  • Automatic and manual failover

• T1 failover
  • • Digium R-Series R850 Digium are the people who make Asterisk, and the Digium R850 provides 8 T1/E1 ports that can be automatically transferred to different endpoints. (This product is completely supported by FreePBX HA)
  • beroNet Failover Switch 4 Port Failoverswitch. Supporting PRI/BRI/FXS/FXO/Ethernet. 2 Modes (Failover and Fallback)
  • beroNet berofos Multiport Failover Switch 4 Port PRI/BRI/Analog/Ethernet Failover Switch controllable via Network
  • Automatic and manual failover

• RS-232/V.35/etc failover
• Most controllable by TCP/IP
• Ethernet failover
  • Absence of packet and loss of Link Signal automatic failover
• generic RJ-45 failover (POTS, PRI, BRI, Ethernet…)
  • ISDNGuard from Junghanns, keep-alive via RS-232
  • beroNet berofos Multiport Failover Switch 4 Port PRI/BRI/Analog/Ethernet Failover Switch controllable via Network
  • Automatic failover and manual failover
• ISP failover
  • Having multiple connections to the Internet from different providers can be a challenging configuration puzzle. Some routers are designed to make this easy for simple installations.
  • See the Small Routers with Multiple WAN Interfaces section in VOIP Routers for more information.

The following is not really a failover type of product, but it might be useful for some people:

• T1/E1 Multiport Repeaters
  • GL Communications Single/Dual Multiport Repeaters.

Description: The single version provides ten identical outputs from a single T1/E1 input. The dual version provides four outputs for each of two inputs. So you could use this to connect one or two T1/E1 to multiple Asterisk servers (where one server would of course not be running Asterisk until the other server is dead)

Software Control of Switches

Most failover switches include software or libraries to control their switches. The majority of these are in the form of Asterisk modules which must be compiled into the local Asterisk installation (requiring the full development toolchain, and all Asterisk source/headers are downloaded). Use of the Asterisk module approach is not ideal for failover scenarios as the module may keep running (eg: watchdog timer) but Asterisk does not process calls.

Some Asterisk clustering solutions include the ability to control the switches above. This allows the clustering software to monitor the health of Asterisk/routes/devices/etc and then make the decision to failover the cluster and connected devices. For example, HAAst ( ((High Availability Asterisk (HAAst) )) ) will control many of the above switches and direct incoming PRI/T1/E1 lines to the active Asterisk peer.