1 00:00:02,040 --> 00:00:05,080 Welcome once again to Implementing Microsoft Windows Always 2 00:00:05,080 --> 00:00:08,190 On VPN, and in this module we're going to talk about high 3 00:00:08,190 --> 00:00:10,940 availability. Up until now, 4 00:00:10,940 --> 00:00:14,280 our infrastructure consists of a single VPN server and a 5 00:00:14,280 --> 00:00:17,170 single NPS server, and while fully functional, 6 00:00:17,170 --> 00:00:21,150 it obviously has some single points of failure. In the event that an 7 00:00:21,150 --> 00:00:24,940 NPS server or a VPN server is offline for any reason, 8 00:00:24,940 --> 00:00:27,970 whether that's a planned outage to apply system updates or an 9 00:00:27,970 --> 00:00:30,540 unplanned outage because of some sort of failure, 10 00:00:30,540 --> 00:00:34,630 the entire solution becomes unavailable and will incur a service outage. 11 00:00:34,630 --> 00:00:38,190 So to eliminate single points of failure, we'll add VPN 12 00:00:38,190 --> 00:00:41,210 and NPS servers to provide redundancy. 13 00:00:41,210 --> 00:00:45,950 This ensures that any time a single server is unavailable for any reason, 14 00:00:45,950 --> 00:00:48,730 either that a planned outage or an unplanned outage, 15 00:00:48,730 --> 00:00:51,490 the service remains viable and users will still be able to 16 00:00:51,490 --> 00:00:54,840 access on‑premises resources remotely. 17 00:00:54,840 --> 00:00:56,150 In addition to redundancy, 18 00:00:56,150 --> 00:01:00,060 administrators may also deploy additional VPN servers, NPS 19 00:01:00,060 --> 00:01:03,510 servers, or commonly both, to provide enough capacity to 20 00:01:03,510 --> 00:01:05,100 meet expected requirements. 21 00:01:05,100 --> 00:01:10,150 A virtual machine provisioned with 4 CPU cores and 8 GB of RAM will usually 22 00:01:10,150 --> 00:01:13,540 support in the neighborhood of about 1,500 concurrent sessions. 23 00:01:13,540 --> 00:01:15,200 Your mileage may vary of course, 24 00:01:15,200 --> 00:01:17,900 but that's a good starting point or a good estimate. 25 00:01:17,900 --> 00:01:22,330 If you plan to, say, support 10,000 concurrent sessions, then you're clearly 26 00:01:22,330 --> 00:01:25,300 going to need additional capacity to meet those needs. 27 00:01:25,300 --> 00:01:29,630 So, in this module, we'll explore the process of adding additional NPS 28 00:01:29,630 --> 00:01:40,000 servers and VPN servers to provide high availability, redundancy, and to meet capacity requirements for our larger deployments.