Host session options
Behind every tab in the portal is a Windows session on a host. This page explains how DartRelay matches tabs to Windows sessions, and the settings on a host's page that change that behaviour.
Tabs and Windows sessions
When a person opens several applications from the same app group on the same host, they all run in one Windows session. Each application gets its own tab, but behind the tabs is one signed-in Windows account, so copy and paste, shared files and open dialogs work between them as they would on a desktop. Opening another application joins that session rather than signing in to Windows again, which is also why the second and later applications open quickly.
What changes from one host to another is how sessions are shared between devices (a phone, a laptop, a second browser), and what happens to a session when its last tab is closed. Windows itself has two relevant rules:
- By default, Windows gives one account one session on a host. A second connection for the same account takes over the first.
- Closing a Remote Desktop window normally leaves the session disconnected, not signed out. Its programs keep running until somebody reconnects, or until Windows ends it after a time limit.
The settings below decide how DartRelay works with those rules. They are on each host's page, under Catalog → Hosts.
A Relay Seat is one device with a live session. One device may run as many applications and desktops as it likes, on as many hosts, for one seat. Settings that give each device its own session therefore do not change how seats are counted. See Licensing and Relay Seats.
Shared Windows logins New in 2.0
When a resource uses Fixed Credentials, several people may be using the same saved Windows account. If they all shared one Windows session, each person would see the others' windows, and closed tabs would leave disconnected sessions piling up for the next visitor to stumble into.
DartRelay recognises a shared login by itself, at the moment someone opens a resource, and handles it without any setting:
| How the resource signs in to the host | Treated as |
|---|---|
| A guest visitor without a sign-in | Always shared |
| Pass-Through (each person's own account) | Never shared |
| Fixed Credentials | Shared, unless exactly one named person can use that saved account: the resource is Only Allowed with a single user (no groups), and no other resource on the host saves the same Windows account |
For a shared login, DartRelay:
- gives each device its own Windows session, so nobody sees anybody else's work; and
- signs the Windows session out when its last tab closes (refreshing the page counts as leaving), so no disconnected session is left behind. This applies to published applications; a full desktop is left disconnected, and the host's time limit ends it.
The first time a shared login is used on a host, DartRelay prepares the host for it in the background with the management account: it allows more than one session per account, and registers the Windows sign-out program in the host's RemoteApp list. If that preparation fails, or a Group Policy setting on the host prevents it, a Shared Windows logins notice appears on the host's page saying so. If a host has no management account, the preparation cannot happen; set one on the host page.
Signing out closes programs without saving. That is why a saved account that only one named person can use is not treated as shared: their work stays in a disconnected session they can return to.
Sessions for the same person New in 2.1
The Sessions for the same person card on the host page decides what happens when one person uses the host from more than one device at once, for example starting on the office PC and carrying on from a laptop. It applies to everyone using the host, shared saved accounts included.
| Choice | What happens | Good for |
|---|---|---|
| Automatic (the default) | A person's own account keeps one session, shared by all their devices; shared logins get one session per device, as described above. The host is kept at one session per account unless a shared login needs more. | Most installations |
| Move to the newest device | One session. When a newer device connects, the session moves to it, and the person's tabs on the other devices show Opened on another device with Reconnect and Close. Reconnect brings the session back to that device. | People who move between computers and want to pick up exactly where they left off |
| Live on every device | One session, shown live on every device the person has it open on at once. | Presenting the same session on two screens |
| A separate session for each device | Each device gets its own Windows session. DartRelay sets the host to allow several sessions per account. | Shared stations and kiosks, or people who deliberately work in two places at once |
When you save a change to this card, DartRelay applies the matching Windows setting to the host straight away (one session per account, or several) and refreshes the host's policy so it takes effect. The save is recorded in the audit log. If a domain Group Policy setting on the host overrides it, the host page says so; change the Group Policy instead.
With Move to the newest device, Reconnect works by opening the application again. A program that allows several copies of itself (Notepad, for example) may then start a second copy beside the one still running in the session.
Ending disconnected sessions New in 2.1
The End disconnected sessions after setting, in the same card, tells Windows how long to keep a disconnected session before ending it. The choices are 15 or 30 minutes; 1, 2, 4 or 8 hours; 1 day; or never. 1 hour is recommended. Leaving it unset keeps whatever the host already has.
This matters most on hosts that allow several sessions per account. When an account has two or more disconnected sessions, Windows asks at sign-in "Select a session to reconnect to". A published application has no way to show that question, so the person sees the application not appear, and about half a minute later Windows gives up and signs the attempt out. A sensible time limit stops disconnected sessions accumulating in the first place.
Like the previous setting, it is applied to the host when you save, by local policy followed by a policy refresh.
Sign out disconnected sessions
The time limit only applies to sessions that disconnect after Windows has the setting. To clear out disconnected sessions that already exist, press Sign out disconnected sessions on the host page's Certificate sign-in card. DartRelay signs out every disconnected session on the host. It never touches active sessions, and never the console or sign-in screen. The action is recorded in the audit log, and the card's check runs again afterwards.
Programs in a disconnected session are closed without saving when it is signed out. Warn people first if they may have unsaved work waiting.
Recommended order on an existing host
- Set End disconnected sessions after to 1 hour and choose how sessions for the same person should behave. Save. The host page reports what the host now has, for example that each account is limited to one session and disconnected sessions end after 1 hour.
- Press Sign out disconnected sessions once, to clear what had already built up.
- Press Check on the same card to confirm the host's settings.
Programs already running get their own tabs New in 2.1
When someone returns to a Windows session that still has programs open in it (from an earlier visit, or from another device), those programs used to appear inside whichever tab they opened, with no tab of their own. Now, a few seconds after the first application appears, DartRelay looks for other programs already running in the session. Each one that matches an application published to that person on the same host gets its own tab, opened in the background so the application they clicked stays in front. Selecting the new tab brings its window forward, and its × closes that program.
Programs that are not published to the person get no tab, and accessories never get one.
Display size
Each session is created at the size of the person's browser window, so the picture is drawn one-to-one and text is as sharp as on a local screen. Resizing the window, or switching to full screen, resizes the session to match, and maximised application windows follow the new size.
The Width and Height settings on each app group and desktop control this:
| Setting | Result |
|---|---|
Both 0 (the default) | The session fits the browser window, and follows it when it changes. Recommended. |
Both set, for example 1920 × 1080 | The session is pinned at that size whatever the window, and the picture is scaled to fit. Use it only for a program that genuinely needs a fixed size. The largest size accepted is 7680 × 4320. |
Set both values or neither; DartRelay always uses them as a pair.
When further applications join a session that is already open, the session keeps the size it was created at by the first tab.
Example: a training room with shared logins
A college runs a training room of twenty PCs. Every PC opens the same accounting program with one saved Windows account, .\trainee, published with Fixed Credentials to everyone.
- DartRelay recognises
.\traineeas a shared login, so each PC gets its own Windows session and nobody sees a neighbour's screen. - When a student closes the last tab, their Windows session is signed out, ready for the next class.
- The administrator sets End disconnected sessions after to 30 minutes, so a PC that is switched off mid-lesson does not leave a session behind for long.
If something goes wrong
| Symptom | Likely cause and fix |
|---|---|
| An application never appears and the tab later closes, mostly for one account | The account has several disconnected sessions and Windows is asking which to reconnect to. Set a time limit and press Sign out disconnected sessions. |
| Opening on a second device ends the session on the first | The host allows one session per account. That is the default; choose another option under Sessions for the same person if you want different behaviour. |
| The host page says a setting is controlled by Group Policy | A domain policy overrides the host's own setting. Change it in Group Policy. |
| A Shared Windows logins notice on the host page | DartRelay could not prepare the host for a shared account. Check the management account and Group Policy, as the notice says. |
| The picture looks soft | Width and Height are set to a fixed size, so the picture is scaled. Set both to 0. On a screen scaled above 100% in Windows display settings, the browser itself enlarges the picture slightly. |
Related pages
Adding and preparing hosts
The management account these settings rely on.
Publishing applications
Pass-Through and Fixed Credentials.
Session lifetimes and idle timeout
How long portal sign-ins and sessions last.
Licensing and Relay Seats
How devices are counted.
Relay Pass
Passwordless Windows logon, and the Certificate sign-in card.