Failover server with another external IP address - ensuring the continuity of services

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Failover server with another external IP address - ensuring the continuity of services

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  1. Windows
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I need to create a configuration in which if one ISP fails, the other ISP will take over. Each server is connected to a different ISP. Each ISP gave an external fixed IP.

What I would like:

- synchronization of services on two servers (mail server, drive server, calendar)

- in the event of a failure of the primary server, the secondary server takes over its functions

It`s possible with Synology?


Edit: Two NAS are in different location
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Typically this would be done at the router (L3) level, with either a fail-over set or load balancing set between your 2 ISPs - the router would have access to both static WAN IPs. For complete redundancy you would have 2 routers too, with a suitable rule in place should one fail. Relatively easy to do on something like an EdgeRouter - they even include a '2 WAN' wizard to get things up and running.

Keeping your 2 severs in sync would be at the switch (L2) level, so easy and painless.
If I didn’t misunderstand what you’re trying to do, then I think this will be a function of the clients. You’ll need to find a way where the clients recognize that the primary server is no longer available and fails over to the secondary server, and when the primary comes online again, the clients switch back. However, synchronization is the challenge here. You don’t want your clients to switch back unless the servers are back in sync.

Did you check SHA? I don’t know much about it. See if the servers can be geographically dispersed (not in the same data center). I doubt it but you can ask Synology.

What you’re asking for is considered an enterprise level solution and usually costs a lot of money.
Package + data sync:
  • Drive ShareSync?
  • MailPlus in HA mode? Not sure about standard Mail Server being kept in sync with another.
  • Calendar?? not got an answer
Dual site failover could be achieved via DNS provided you have an Internet based service that monitors each site and determines resolution on primary availability. Features along the lines of those found in F5 BIG-IP DNS (formerly GTM, Global Traffic Management).

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