User`s guide

VigorTalk ATA24 Series User’s Guide
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Secondary DNS Sets the private IP address of the secondary DNS.
Lease Time (Min) Sets a lease time for the DHCP server. The time unit is minute.
Gateway IP (Optional) Sets a gateway IP address for the DHCP server.
Click Apply to reboot the system and apply the settings.
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The High Availability (HA) feature refers to the awareness of component failure and the
availability of backup resources. The complexity of HA is determined by the availability needs
and the tolerance of system interruptions. Systems, that provide nearly full-time availability,
typically have redundant hardware and software that makes the system available despite
failures.
The high availability is designed to avoid single points-of-failure. When failures occur, the
failover process moves processing performed by the failed component (the “Master”) to the
backup component (the “Slave”). This process remains system-wide resources, recovers
partial of failed transactions, and restores the system to normal within a matter of
microseconds.
Take the following picture as an example. The left device is regarded as Master device, the
right device is regarded as Slave device. When Master device is broken down, the Slave
device could replace the Master role to take over all jobs as soon as possible. However, once
the original Master is working again, the Slave would be changed to original role to stand by.
In the Network group, click the High availability option.