Distributed locking in .NET

Question

I'm looking for recommendations for a locking mechanism that will work across multiple machines. In my case I basically just want to be able to start a service on 2 machines and have one block until the other finishes as a simple way to insure redundancy in case a service machine goes down.

Sort of along the same lines as Distributed Lock Service but specifically looking for projects that people have successfully integrated with .NET.

Answer 1

We use SqlServer's application lock functionality for distributed locking. This is especially convenient if SqlServer is already a part of your stack.

To make this easier to work with from .NET, I created a NuGet package which makes it easy to use this functionality. The library also supports other backends such as Postgres, Azure blob storage, and Redis.

With this library, the code looks like:

var @lock = new SqlDistributedLock("my_lock_name", connectionString);
using (@lock.Acquire())
{
   // critical region
}

Because the underlying SqlServer functionality is very flexible, there are also overloads supporting TryAcquire semantics, timeouts, and async locking.

Answer 2

If you are using AppFabric for Windows Server, you can use this DataCache extension. You can also use redis locks with ServiceStack's redis client.

Both are .NET implementations but require a server component. I've been tinkering with a PeerChannel implementation of a distributed lock that uses peer to peer communication and doesn't require any server infrastructure. Let me know if this is something you would be interested in.