> For the complete documentation index, see [llms.txt](https://docs.gotempest.app/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.gotempest.app/connect-to-servers/ssh-connection-multiplexing.md).

# SSH Connection Multiplexing

Tempest's **connection multiplexing** reuses one authenticated SSH connection across multiple sessions to the same host. New tabs to the same server open *instantly* — no second TCP handshake, no second SSH key exchange, no second MFA prompt — because Tempest opens additional channels on the existing connection.

This is the same idea as OpenSSH's `ControlMaster auto` / `ControlPath`, but built in and enabled with one toggle.

## Enable it

1. Edit your SSH host → **Transport** section.
2. Toggle **Connection multiplexing** on.
3. Save and reconnect.

The first connection authenticates normally. Every subsequent tab to the same host opens a new SSH `session` channel on the same authenticated connection — usually < 50 ms versus seconds for a fresh handshake.

## Why this is a big deal

* **Instant new tabs** to a frequently-used server.
* **One MFA prompt per host**, not per session — especially valuable for YubiKey / FIDO2 hosts where you'd otherwise tap-tap-tap per tab.
* **Faster SFTP**: opening the SFTP browser doesn't kick off a fresh handshake.
* **Lower load on the server**: one TCP socket and one auth event per active host, regardless of how many tabs you have open.

## When NOT to enable it

* If your server has aggressive `MaxSessions` limits and you frequently fan out many sessions per connection.
* When using [Mosh](/connect-to-servers/mosh-mobile-shell.md) — Mosh closes the SSH channel after bootstrap, so multiplexing has nothing to share.
* For one-off connections where you'll never open a second tab anyway (no benefit, slight memory cost).

## Pro feature

Connection multiplexing requires **Tempest Pro**.

## Compared to OpenSSH `ControlMaster`

| Feature                                   | OpenSSH `ControlMaster`                                                  | Tempest                              |
| ----------------------------------------- | ------------------------------------------------------------------------ | ------------------------------------ |
| Setup                                     | Add `ControlMaster auto` + `ControlPath ~/.ssh/cm/%C` to `~/.ssh/config` | Toggle in host edit form             |
| Persistence across runs                   | Yes (until socket times out)                                             | Per-Tempest-process                  |
| GUI to see active multiplexed connections | None                                                                     | Connection panel shows session count |

## Combine with jump hosts

Multiplexing works through [jump host chains](/connect-to-servers/ssh-jump-host-bastion-chaining.md) — the chain is built once for the first session, and subsequent sessions reuse the entire chain. Particularly useful for "I have to bounce through 3 bastions to reach prod" workflows.

## See also

* [SSH Jump Host & Bastion Chaining](/connect-to-servers/ssh-jump-host-bastion-chaining.md)
* [YubiKey & FIDO2 SSH Authentication](/authentication/yubikey-fido2-ssh-authentication.md) — multiplexing means one tap per host instead of per session