I use a console app and connect to Couchbase thought VPN. About server I can’t say anything, but all works on SDK 2.7 with port.
2020-06-20T00:08:15.0910020+03:00 [DBG] Bootstrapping with node "192.168.1.120" (98ca0e33)
2020-06-20T00:08:15.2618440+03:00 [DBG] Setting TCP Keep-Alives using SocketOptions - enable keep-alives True, time 00:01:00, interval 00:00:01. (d66a37aa)
2020-06-20T00:08:15.2618439+03:00 [DBG] Setting TCP Keep-Alives using SocketOptions - enable keep-alives True, time 00:01:00, interval 00:00:01. (d66a37aa)
2020-06-20T00:08:15.2816599+03:00 [DBG] Starting connection initialization on server "192.168.1.120:8091". (5c5836f0)
2020-06-20T00:08:15.2818617+03:00 [DBG] Starting connection initialization on server "192.168.1.120:8091". (5c5836f0)
2020-06-20T00:08:15.4645288+03:00 [DBG] Executing op Helo on "192.168.1.120:8091" with key "{\"i\":\"a410cf205bacf4a5/0000000000000001\",\"a\":\"couchbase-net-sdk/3.0.2.0 (clr/.NET Core 3.1.3) (os/Microsoft Windows 10.0.18363)\"}" and opaque 3. (ebdc59ba)
2020-06-20T00:08:15.4645234+03:00 [DBG] Executing op Helo on "192.168.1.120:8091" with key "{\"i\":\"a410cf205bacf4a5/0000000000000002\",\"a\":\"couchbase-net-sdk/3.0.2.0 (clr/.NET Core 3.1.3) (os/Microsoft Windows 10.0.18363)\"}" and opaque 4. (ebdc59ba)
2020-06-20T00:08:17.9765313+03:00 [DBG] KV Operation timeout for "{\"i\":\"a410cf205bacf4a5/0000000000000002\",\"a\":\"couchbase-net-sdk/3.0.2.0 (clr/.NET Core 3.1.3) (os/Microsoft Windows 10.0.18363)\"}" on server "192.168.1.120:8091". (d607be31)
2020-06-20T00:08:17.9765313+03:00 [DBG] KV Operation timeout for "{\"i\":\"a410cf205bacf4a5/0000000000000001\",\"a\":\"couchbase-net-sdk/3.0.2.0 (clr/.NET Core 3.1.3) (os/Microsoft Windows 10.0.18363)\"}" on server "192.168.1.120:8091". (d607be31)
2020-06-20T00:08:18.0203175+03:00 [DBG] Error encountered bootstrapping cluster; if the cluster is 6.5 or earlier, this can be ignored. "System.Threading.Tasks.TaskCanceledException: A task was canceled.
at Couchbase.Core.ClusterNode.ExecuteOp(Action`3 sender, IOperation op, Object state, CancellationToken token, Nullable`1 timeout)
at Couchbase.Core.ClusterNode.Hello(IConnection connection, CancellationToken cancellationToken)
at Couchbase.Core.ClusterNode.Couchbase.Core.IO.Connections.IConnectionInitializer.InitializeConnectionAsync(IConnection connection, CancellationToken cancellationToken)
at Couchbase.Core.IO.Connections.ConnectionPoolBase.CreateConnectionAsync(CancellationToken cancellationToken)
at Couchbase.Core.IO.Connections.DataFlow.DataFlowConnectionPool.<>c__DisplayClass28_0.<<AddConnectionsAsync>g__StartConnection|0>d.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
at Couchbase.Core.IO.Connections.DataFlow.DataFlowConnectionPool.AddConnectionsAsync(Int32 count, CancellationToken cancellationToken)
at Couchbase.Core.IO.Connections.DataFlow.DataFlowConnectionPool.InitializeAsync(CancellationToken cancellationToken)
at Couchbase.Core.ClusterNode.InitializeAsync()
at Couchbase.Core.DI.ClusterNodeFactory.CreateAndConnectAsync(HostEndpoint endPoint, BucketType bucketType, NodeAdapter nodeAdapter, CancellationToken cancellationToken)
at Couchbase.Core.ClusterContext.BootstrapGlobalAsync()
at Couchbase.Cluster.Couchbase.Core.Bootstrapping.IBootstrappable.BootStrapAsync()". (ba6fd600)
2020-06-20T00:08:18.1070995+03:00 [DBG] Setting TCP Keep-Alives using SocketOptions - enable keep-alives True, time 00:01:00, interval 00:00:01. (d66a37aa)
2020-06-20T00:08:18.1072854+03:00 [DBG] Starting connection initialization on server "192.168.1.120:8091". (5c5836f0)
2020-06-20T00:08:18.1075981+03:00 [DBG] Executing op Helo on "192.168.1.120:8091" with key "{\"i\":\"a410cf205bacf4a5/0000000000000003\",\"a\":\"couchbase-net-sdk/3.0.2.0 (clr/.NET Core 3.1.3) (os/Microsoft Windows 10.0.18363)\"}" and opaque 6. (ebdc59ba)
2020-06-20T00:08:18.1178018+03:00 [DBG] Setting TCP Keep-Alives using SocketOptions - enable keep-alives True, time 00:01:00, interval 00:00:01. (d66a37aa)
2020-06-20T00:08:18.1179569+03:00 [DBG] Starting connection initialization on server "192.168.1.120:8091". (5c5836f0)
2020-06-20T00:08:18.1181311+03:00 [DBG] Executing op Helo on "192.168.1.120:8091" with key "{\"i\":\"a410cf205bacf4a5/0000000000000004\",\"a\":\"couchbase-net-sdk/3.0.2.0 (clr/.NET Core 3.1.3) (os/Microsoft Windows 10.0.18363)\"}" and opaque 8. (ebdc59ba)
2020-06-20T00:08:20.6083771+03:00 [DBG] KV Operation timeout for "{\"i\":\"a410cf205bacf4a5/0000000000000003\",\"a\":\"couchbase-net-sdk/3.0.2.0 (clr/.NET Core 3.1.3) (os/Microsoft Windows 10.0.18363)\"}" on server "192.168.1.120:8091". (d607be31)
2020-06-20T00:08:20.6311004+03:00 [DBG] KV Operation timeout for "{\"i\":\"a410cf205bacf4a5/0000000000000004\",\"a\":\"couchbase-net-sdk/3.0.2.0 (clr/.NET Core 3.1.3) (os/Microsoft Windows 10.0.18363)\"}" on server "192.168.1.120:8091". (d607be31)
2020-06-20T00:08:20.6343093+03:00 [INF] Cannot bootstrap bucket "AtomicSearchCache" as Couchbase. (1ecb21a9)
System.Threading.Tasks.TaskCanceledException: A task was canceled.
at Couchbase.Core.ClusterNode.ExecuteOp(Action`3 sender, IOperation op, Object state, CancellationToken token, Nullable`1 timeout)
at Couchbase.Core.ClusterNode.Hello(IConnection connection, CancellationToken cancellationToken)
at Couchbase.Core.ClusterNode.Couchbase.Core.IO.Connections.IConnectionInitializer.InitializeConnectionAsync(IConnection connection, CancellationToken cancellationToken)
at Couchbase.Core.IO.Connections.ConnectionPoolBase.CreateConnectionAsync(CancellationToken cancellationToken)
at Couchbase.Core.IO.Connections.DataFlow.DataFlowConnectionPool.<>c__DisplayClass28_0.<<AddConnectionsAsync>g__StartConnection|0>d.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
at Couchbase.Core.IO.Connections.DataFlow.DataFlowConnectionPool.AddConnectionsAsync(Int32 count, CancellationToken cancellationToken)
at Couchbase.Core.IO.Connections.DataFlow.DataFlowConnectionPool.InitializeAsync(CancellationToken cancellationToken)
at Couchbase.Core.ClusterNode.InitializeAsync()
at Couchbase.Core.DI.ClusterNodeFactory.CreateAndConnectAsync(HostEndpoint endPoint, BucketType bucketType, NodeAdapter nodeAdapter, CancellationToken cancellationToken)
at Couchbase.Core.ClusterContext.CreateAndBootStrapBucketAsync(String name, HostEndpoint endpoint, BucketType type)
at Couchbase.Core.ClusterContext.GetOrCreateBucketAsync(String name)
2020-06-20T00:08:20.7645506+03:00 [DBG] Setting TCP Keep-Alives using SocketOptions - enable keep-alives True, time 00:01:00, interval 00:00:01. (d66a37aa)
2020-06-20T00:08:20.7646071+03:00 [DBG] Setting TCP Keep-Alives using SocketOptions - enable keep-alives True, time 00:01:00, interval 00:00:01. (d66a37aa)
2020-06-20T00:08:20.7647420+03:00 [DBG] Starting connection initialization on server "192.168.1.120:8091". (5c5836f0)
2020-06-20T00:08:20.7647422+03:00 [DBG] Starting connection initialization on server "192.168.1.120:8091". (5c5836f0)
2020-06-20T00:08:20.7653749+03:00 [DBG] Executing op Helo on "192.168.1.120:8091" with key "{\"i\":\"a410cf205bacf4a5/0000000000000005\",\"a\":\"couchbase-net-sdk/3.0.2.0 (clr/.NET Core 3.1.3) (os/Microsoft Windows 10.0.18363)\"}" and opaque 11. (ebdc59ba)
2020-06-20T00:08:20.7653749+03:00 [DBG] Executing op Helo on "192.168.1.120:8091" with key "{\"i\":\"a410cf205bacf4a5/0000000000000006\",\"a\":\"couchbase-net-sdk/3.0.2.0 (clr/.NET Core 3.1.3) (os/Microsoft Windows 10.0.18363)\"}" and opaque 12. (ebdc59ba)
2020-06-20T00:08:23.2665223+03:00 [DBG] KV Operation timeout for "{\"i\":\"a410cf205bacf4a5/0000000000000005\",\"a\":\"couchbase-net-sdk/3.0.2.0 (clr/.NET Core 3.1.3) (os/Microsoft Windows 10.0.18363)\"}" on server "192.168.1.120:8091". (d607be31)
2020-06-20T00:08:23.2665223+03:00 [DBG] KV Operation timeout for "{\"i\":\"a410cf205bacf4a5/0000000000000006\",\"a\":\"couchbase-net-sdk/3.0.2.0 (clr/.NET Core 3.1.3) (os/Microsoft Windows 10.0.18363)\"}" on server "192.168.1.120:8091". (d607be31)
2020-06-20T00:08:23.2684301+03:00 [INF] Cannot bootstrap bucket "AtomicSearchCache" as Memcached. (1ecb21a9)
System.Threading.Tasks.TaskCanceledException: A task was canceled.
at Couchbase.Core.ClusterNode.ExecuteOp(Action`3 sender, IOperation op, Object state, CancellationToken token, Nullable`1 timeout)
at Couchbase.Core.ClusterNode.Hello(IConnection connection, CancellationToken cancellationToken)
at Couchbase.Core.ClusterNode.Couchbase.Core.IO.Connections.IConnectionInitializer.InitializeConnectionAsync(IConnection connection, CancellationToken cancellationToken)
at Couchbase.Core.IO.Connections.ConnectionPoolBase.CreateConnectionAsync(CancellationToken cancellationToken)
at Couchbase.Core.IO.Connections.DataFlow.DataFlowConnectionPool.<>c__DisplayClass28_0.<<AddConnectionsAsync>g__StartConnection|0>d.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
at Couchbase.Core.IO.Connections.DataFlow.DataFlowConnectionPool.AddConnectionsAsync(Int32 count, CancellationToken cancellationToken)
at Couchbase.Core.IO.Connections.DataFlow.DataFlowConnectionPool.InitializeAsync(CancellationToken cancellationToken)
at Couchbase.Core.ClusterNode.InitializeAsync()
at Couchbase.Core.DI.ClusterNodeFactory.CreateAndConnectAsync(HostEndpoint endPoint, BucketType bucketType, NodeAdapter nodeAdapter, CancellationToken cancellationToken)
at Couchbase.Core.ClusterContext.CreateAndBootStrapBucketAsync(String name, HostEndpoint endpoint, BucketType type)
at Couchbase.Core.ClusterContext.GetOrCreateBucketAsync(String name)
2020-06-20T00:08:23.3654539+03:00 [DBG] Setting TCP Keep-Alives using SocketOptions - enable keep-alives True, time 00:01:00, interval 00:00:01. (d66a37aa)
2020-06-20T00:08:23.3654539+03:00 [DBG] Setting TCP Keep-Alives using SocketOptions - enable keep-alives True, time 00:01:00, interval 00:00:01. (d66a37aa)
2020-06-20T00:08:23.3658702+03:00 [DBG] Starting connection initialization on server "192.168.1.120:8091". (5c5836f0)
2020-06-20T00:08:23.3662523+03:00 [DBG] Executing op Helo on "192.168.1.120:8091" with key "{\"i\":\"a410cf205bacf4a5/0000000000000008\",\"a\":\"couchbase-net-sdk/3.0.2.0 (clr/.NET Core 3.1.3) (os/Microsoft Windows 10.0.18363)\"}" and opaque 14. (ebdc59ba)
2020-06-20T00:08:23.3675753+03:00 [DBG] Starting connection initialization on server "192.168.1.120:8091". (5c5836f0)
2020-06-20T00:08:23.3682978+03:00 [DBG] Executing op Helo on "192.168.1.120:8091" with key "{\"i\":\"a410cf205bacf4a5/0000000000000007\",\"a\":\"couchbase-net-sdk/3.0.2.0 (clr/.NET Core 3.1.3) (os/Microsoft Windows 10.0.18363)\"}" and opaque 16. (ebdc59ba)
2020-06-20T00:08:25.8765751+03:00 [DBG] KV Operation timeout for "{\"i\":\"a410cf205bacf4a5/0000000000000008\",\"a\":\"couchbase-net-sdk/3.0.2.0 (clr/.NET Core 3.1.3) (os/Microsoft Windows 10.0.18363)\"}" on server "192.168.1.120:8091". (d607be31)
2020-06-20T00:08:25.8766088+03:00 [DBG] KV Operation timeout for "{\"i\":\"a410cf205bacf4a5/0000000000000007\",\"a\":\"couchbase-net-sdk/3.0.2.0 (clr/.NET Core 3.1.3) (os/Microsoft Windows 10.0.18363)\"}" on server "192.168.1.120:8091". (d607be31)
2020-06-20T00:08:25.8782770+03:00 [INF] Cannot bootstrap bucket "AtomicSearchCache" as Ephemeral. (1ecb21a9)
System.Threading.Tasks.TaskCanceledException: A task was canceled.
at Couchbase.Core.ClusterNode.ExecuteOp(Action`3 sender, IOperation op, Object state, CancellationToken token, Nullable`1 timeout)
at Couchbase.Core.ClusterNode.Hello(IConnection connection, CancellationToken cancellationToken)
at Couchbase.Core.ClusterNode.Couchbase.Core.IO.Connections.IConnectionInitializer.InitializeConnectionAsync(IConnection connection, CancellationToken cancellationToken)
at Couchbase.Core.IO.Connections.ConnectionPoolBase.CreateConnectionAsync(CancellationToken cancellationToken)
at Couchbase.Core.IO.Connections.DataFlow.DataFlowConnectionPool.<>c__DisplayClass28_0.<<AddConnectionsAsync>g__StartConnection|0>d.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
at Couchbase.Core.IO.Connections.DataFlow.DataFlowConnectionPool.AddConnectionsAsync(Int32 count, CancellationToken cancellationToken)
at Couchbase.Core.IO.Connections.DataFlow.DataFlowConnectionPool.InitializeAsync(CancellationToken cancellationToken)
at Couchbase.Core.ClusterNode.InitializeAsync()
at Couchbase.Core.DI.ClusterNodeFactory.CreateAndConnectAsync(HostEndpoint endPoint, BucketType bucketType, NodeAdapter nodeAdapter, CancellationToken cancellationToken)
at Couchbase.Core.ClusterContext.CreateAndBootStrapBucketAsync(String name, HostEndpoint endpoint, BucketType type)
at Couchbase.Core.ClusterContext.GetOrCreateBucketAsync(String name)