Check if two lists are equal

I have a class as follows:

public class Tag {
    public Int32 Id { get; set; }
    public String Name { get; set; }
}

And I have two lists of tag:

List<Tag> tags1;
List<Tag> tags2;

I used LINQ’s select to get the Ids of each tags list. And then:

List<Int32> ids1 = new List<Int32> { 1, 2, 3, 4 };
List<Int32> ids2 = new List<Int32> { 1, 2, 3, 4 };
List<Int32> ids3 = new List<Int32> { 2, 1, 3, 4 };
List<Int32> ids4 = new List<Int32> { 1, 2, 3, 5 };
List<Int32> ids5 = new List<Int32> { 1, 1, 3, 4 };

ids1 should be equal to ids2 and ids3 … Both have the same numbers.

ids1 should not be equal to ids4 and to ids5 …

I tried the following:

var a = ints1.Equals(ints2);
var b = ints1.Equals(ints3);

But both give me false.

What is the fastest way to check if the lists of tags are equal?

UPDATE

I am looking for POSTS which TAGS are exactly the same as the TAGS in a BOOK.

IRepository repository = new Repository(new Context());

IList<Tags> tags = new List<Tag> { new Tag { Id = 1 }, new Tag { Id = 2 } };

Book book = new Book { Tags = new List<Tag> { new Tag { Id = 1 }, new Tag { Id = 2 } } };

var posts = repository
  .Include<Post>(x => x.Tags)
  .Where(x => new HashSet<Int32>(tags.Select(y => y.Id)).SetEquals(book.Tags.Select(y => y.Id)))
  .ToList();

I am using Entity Framework and I get the error:

An exception of type ‘System.NotSupportedException’ occurred in mscorlib.dll but was not handled in user code

Additional information: LINQ to Entities does not recognize the method ‘Boolean SetEquals(System.Collections.Generic.IEnumerable`1[System.Int32])’ method, and this method cannot be translated into a store expression.

How do I solve this?