[ENG] 8.3. [DKSF 48.5 IU] What is "Watchdog" and Can it Be Configured?
«Watchdog» — is a specific operation mode of a relay channel. In this mode, specified addresses are pinged by ping (ICMP Echo) with a set frequency. If there is no response, the power is switched off for short term thus rebooting a device that is connected to the terminals of the relay.
If indicated IP addresses are outside the IP subnetwork of a device, there is a need to specify a gateway address at the page «SETUP» of the device web interface to access the external network.
In order to use the «Watchdog» module, the relay control must be switched to "Watchdog" mode on the "AC OUTLETS" page of the device’s web interface. To configure the "Watchdog", you must press the "Watchdog" button which located on any of the eight control channels of the built-in relay:
All module settings are carried out in a pop up dialogue:
Enable Control of Relay — the activation of the relay control.If the checkbox is not installed, the relay will not be controlled from the "Watchdog" module.In Default: the checkbox is not installed.
Polling the Address A, B, C - a set of checkboxes that allow you to set the addresses participating in the poll individually. In default: checkboxes are not installed.
If no checkbox is installed or IP addresses are not set for installed checkboxes, the poll will not be carried out and the "Watchdog" mode will be practically disabled.
Address A (B, C) — is an entry field to view or change polling addresses. It is acceptable to indicate either IP-address or a domain name. It is possible to configure up to three addresses. An empty field disables polling. In default: address is not specified.
Reset Counter (cleared on firmware reboot) — is an informational field that shows how many times a channel was rebooted as a result of the actions of the module «Watchdog». A counter does not take into account the number of reboots in the «manual mode». A counter is cleared when a NetPing device is de-energized.
Ping Polling Period, s (10–300) — is a field for setting the time interval after which repeated ICMP Echo (ping) is sent to the specified IP addresses after receiving a response from them. In Default: 15 sec.
Ping Timeout, ms (600–9000) — is a field for setting a timeout before the repetion of ICMP Echo (ping) . The value should not exceed the usual time of the response to the ICMP Echo (ping) for this network with some reserve to ensure avoiding false positives of the module «Watchdog». In default: 1000 ms.
Max Ping Repeats After Timeout -is a field for setting a maximum number of attempts to get a response to «ping». If a number of attempts is over, an IP address is considered «silent». It is desirable that the ping polling period exceeds the ping timeout multiplied by the maximum number of attempts. If this condition is not fulfilled, then a new polling cycle will be postponed until the specified number of attempts is over. In Default: 8.
Reset Duration, s (12–900) — is a field for setting the time needed for a connected to the power supply device is deenergized to initiate reset and reboot. In default: 12 s.
Ping Polling Pause After Reset, s (1–3600) — a field for setting the time for which polling is suspended after turning on the power channel socket. A pause is necessary for the device to reboot, initialize and restore the functioning of its network interfaces. Otherwise, an endless repetition of the operation of the "Watchdog" module is possible. In Default: 15 s.
Limit Number of Reset Retries (0 Disable, 1–255) — is a field for setting the number of consequent unsuccessful resets, after which functioning of the «load» is not restored and there is still no response to ping. This can happen at the stable failure of the «load» that is impossible to restore by switching the power on and off. When the limit of repeats is reached, resets are stopped, but a periodic ping request continues. Resets are unlocked when there is a response on ping. Resets are stopped and a regular operation order is restored after a response to ping and everything is recorded in the log. Parameter value 0 disables the limit. In Default: 0.
Reset Polarity —is a field that allows indicating what action is going to be done to reboot the connected loadat outcoming terminals: «Switch Relay Off» or «Switch Relay On» In default: Switch Relay Off.
Reset Condition Logic — determines a condition at which a device connected to terminals is going to be rebooted.
No reply from any of Address A, B, C — a connected device will be rebooted if at least one of addresses did not respond.
No reply from all of Address A, B, C — a connected device will be rebooted only if all requested addresses did not respond.
No reply from Address A and from one of B, C — a connected device will be rebooted if address А and any of addresses В or С, or both B and C did not respond.
No reply from Address A, but B or C replies — connected device will be rebooted only if address A did not respond but address B and/or address C responded. So, if all addresses do not respond, a connected device will not be rebooted.
After setting all necessary parameters, click the button «Apply changes», so that a device executes a command.
If one of the parameters is set incorrectly, it will be highlighted in red:
There is a need to correct a parameter value and click the button «Apply changes» one more time.
To understand the configuration process of the «Watchdog» module better, it is possible to read the article here http://www.netpingdevice.com/blog/avtomaticheskaya-perezagruzka-zavisayushhego-routera-podklyuchennogo-k-netping-2-pwr-220-v3-eth