The way to set an fixed expiration time span is to set the ExpireTimeSpan
property in your Startup.Auth.cs
file like this:
// Enable the application to use a cookie to store information for the signed in user
app.UseCookieAuthentication(new CookieAuthenticationOptions
{
AuthenticationType = DefaultAuthenticationTypes.ApplicationCookie,
LoginPath = new PathString("/Account/Login"),
ExpireTimeSpan = TimeSpan.FromDays(2)
});
Note that you'll also have to set the cookie to persist. In your code you'll have to pass in a bool in addition to the username and password, and then change
authenticationManager.SignIn(id);
to be
authenticationManager.SignIn(new AuthenticationProperties { IsPersistent = rememberMe }, id);