var azs = Pulumi.Aws.GetAvailabilityZones.InvokeAsync(new Pulumi.Aws.GetAvailabilityZonesArgs()).Result;
var hostnames = new List<Input<string>>();
var ips = new List<Input<string>>();
foreach (var az in azs.Names)
{
    var server = new Pulumi.Aws.Ec2.Instance($"web-server-{az}", new Pulumi.Aws.Ec2.InstanceArgs
    {
        InstanceType = "t2.micro",
        VpcSecurityGroupIds = {group.Id},
        UserData = userData,
        Ami = ami.Apply(a => a.Id),
        AvailabilityZone = az,
    });

    hostnames.Add(server.PublicDns);
    ips.Add(server.PublicIp);
}