Communication parameters and timer settings
This chapter will cover the different communication parameters and timer settings which are configurable in Hot Standby of anynode.
Minimum Link Retry Timeout
The anynode instance configured as the hot standby main system attempts to establish a network connection to the standby system. Should this connection attempt fail, anynode will retry with intervals that double with each failure. This setting determines the minimum boundary for these retry intervals.
Maximum Link Retry Timeout
Like the minimum timeout, this setting controls the maximum boundary for the retry intervals between connection attempts by the anynode main system to the standby system. The retry intervals increase and are capped at this maximum value.
Link Ping Interval
While the anynode main system maintains an active network connection to the standby system, it sends regular control messages across this connection. These messages signal to the standby system that the main system is operational. The interval at which these messages are sent is controlled by this setting. Changing this interval from its default may affect the reliability of the hot standby setup, so adjustments should only be made following guidance from TE-SYSTEMS support personnel.
Link Standby Timeout
This setting determines how long the standby system waits after the last received control message before considering the main system as down and assuming the active role. Modifying this timeout from its default setting can influence the stability of the hot standby feature, and as such, changes should be made under advisement from TE-SYSTEMS support.
Handover Hold Timeout
When the main anynode decides to hand over the active role to the standby system, it typically does so immediately. However, this timeout provides a brief delay to ensure the stability of the conditions triggering the handover, preventing rapid or frequent reversals of roles.
Recovery Hold Timeout
Similar to the handover hold, this setting allows a brief delay when the main anynode determines to recover the active role from the standby system. This delay helps verify the stability of the conditions under which the role recovery occurs, preventing frequent role changes.
Recovery Timeout
This timeout controls how long the main system waits before assuming that the recovery of the active role from the standby system has been successful. This allows the standby system some time to complete any necessary shutdown processes. If these processes take too long, the setting ensures that neither system remains inactive indefinitely.
These settings are crucial for managing the behavior of anynode in a hot standby configuration and should be configured carefully to maintain system stability and reliability.