{"action":"opened","issue":{"url":"https://api.github.com/repos/IdentityServer/IdentityServer3/issues/2333","labels_url":"https://api.github.com/repos/IdentityServer/IdentityServer3/issues/2333/labels{/name}","comments_url":"https://api.github.com/repos/IdentityServer/IdentityServer3/issues/2333/comments","events_url":"https://api.github.com/repos/IdentityServer/IdentityServer3/issues/2333/events","html_url":"https://github.com/IdentityServer/IdentityServer3/issues/2333","id":123596638,"number":2333,"title":"Check session endpoint enabled, but SessionId is missing","user":{"login":"parkinsona","id":8508456,"avatar_url":"https://avatars.githubusercontent.com/u/8508456?v=3","gravatar_id":"","url":"https://api.github.com/users/parkinsona","html_url":"https://github.com/parkinsona","followers_url":"https://api.github.com/users/parkinsona/followers","following_url":"https://api.github.com/users/parkinsona/following{/other_user}","gists_url":"https://api.github.com/users/parkinsona/gists{/gist_id}","starred_url":"https://api.github.com/users/parkinsona/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/parkinsona/subscriptions","organizations_url":"https://api.github.com/users/parkinsona/orgs","repos_url":"https://api.github.com/users/parkinsona/repos","events_url":"https://api.github.com/users/parkinsona/events{/privacy}","received_events_url":"https://api.github.com/users/parkinsona/received_events","type":"User","site_admin":false},"labels":[],"state":"open","locked":false,"assignee":null,"milestone":null,"comments":0,"created_at":"2015-12-23T03:25:35Z","updated_at":"2015-12-23T03:25:35Z","closed_at":null,"body":"We have had identityserver in production for about 6 months and just recently (past month and a half) it has started to return the error: \"Check session endpoint enabled, but SessionId is missing\".\r\n\r\nThis is only happening in our production environment. Which was moved to a different data centre around the same time the issue started happening. Having said that, we had an increase in usage of the site at the same time too. Both our UAT and PROD environments are load balanced and were moved at the same time.\r\n\r\nWe haven't been able to replicate it, but we know that it happens when the idsvr cookie is still active, but the idsvr.session cookie is dead. I'm not sure how it could get into this state though.I am yet to determine if its being caused by the \"remember me\" functionality or not.\r\n\r\nThis is the setting for cookie options in our IdentityServer host. Expire Time span is 1 hour.\r\n\r\n``` c#\r\nCookieOptions = new Thinktecture.IdentityServer.Core.Configuration.CookieOptions   \r\n                        {\r\n                            SlidingExpiration = true,                           \r\n                            ExpireTimeSpan = Settings.Default.ExpireTimeSpan\r\n                        }\r\n```\r\nDoes this cookie setting cover both the idsvr & idsvr.session cookies that are created? Is it possible that the idsvr cookie is sliding but the idsvr.session cookie is not?\r\n\r\nIs there a reason why identityserver doesn't redirect you to the login page when you get into this situation?\r\n\r\nThanks again for your help and support on this product.\r\n"}}