known_hosts, and ~/.ssh/config remain the source of connection settings —
Cogno does not manage keys for you.
Before you start
- Confirm
ssh <destination>works from your computer without a password prompt. - Include the ssh username, for example
deploy@build-01. - On macOS servers, turn on System Settings → General → Sharing → Remote Login.
Set up a new server
Use the Set up a new server card at the bottom of Settings → Machines. It takes an ssh destination and turns the server into a registered, connected machine.1
Enter the server
Under New server ssh destination, enter the destination you already use —
for example
deploy@build-01 — and pick Claude Code or Codex under
Choose the coding engine.2
Set up server
Select Set up server. Cogno streams progress through each step:
Checking the server, Installing the Cogno CLI, Reading the machine
identity, Issuing the credential, Registering the daemon, and
Connecting.
3
Done
When setup finishes the server appears under Your machines, already
connected and ready to run work.
Setting up the coding engine is separate from registering the server. If the
engine cannot be installed, the server itself still finishes setup and connects.
Connect to a registered server
A server that is already registered — by you earlier, or from another computer with the same account — is connected from its row in Your machines.1
Find the machine
Open Settings → Machines and find the server under Your machines.
2
Enter the ssh destination
Enter the destination in the row’s field (
user@host or ssh alias). It is
reached over your own ssh — your keys, config aliases and known hosts apply.3
Connect
Select Connect. The row shows Tunnel connected · <destination>
when the server is reachable.
Several people on one server
A machine is one OS account on one host. When several people use the same server, each person sets it up with their own OS account and ssh destination, and each account appears as its own machine. When two machines report the same name, the row also shows the OS account so you can tell them apart.Open a port the server is listening on
A dev server you start on a remote machine listens on that machine’slocalhost,
not yours — so the http://localhost:5173 its output prints does not open in your
browser. The Ports tab beside the Task’s terminal forwards it over the
connection Cogno already holds and opens it for you.
The tab appears only for a Task running on another machine. Work on this computer
already answers at localhost, so there is nothing to forward.
1
Open the Ports tab
In the Task’s terminal strip, select Ports. Cogno asks the machine what it
is listening on and lists it under Port, Forwarded Address, and
Running Process.
2
Open a port
Select a row. Cogno forwards it and opens it in your browser. Forwarded
Address then shows the address on this computer — normally the same number,
so
http://localhost:5173 on the server is http://localhost:5173 here too.3
Come back to it
Hover a forwarded row for Copy address, Open in browser, and Stop
forwarding. The count on the Ports tab is how many are forwarded.
Ports the list does not show
The list holds what the machine reports listening on above port 1024. Use Add port for anything else — a port below 1024, or a service the machine does not report, such as a container reached through a published port. It takes a number or an address and a port, as the field says:5173 or 10.0.0.4:5173.
A port added this way is a row like any other, and stays until you stop forwarding
it or the connection to the machine ends.
Running Process is what the machine named for the socket. On Linux it names
only processes belonging to your own account, so the column is often empty.If the same number is already in use on your computer, Cogno forwards to a
different one and Forwarded Address shows which. Forwarding works from macOS
and Linux; on Windows the app asks you to use one of those.
Collect Engine logs from a machine
Every machine under Your machines runs the Cogno Engine, the background service that checks in with Cogno and runs agent work. When a machine misbehaves, you can read its Engine log from your own computer instead of signing in to the box. This works for any machine on the list — this computer, a remote server, or a headless install — as long as it is checking in.1
Open the machine's logs
In Your machines, select the row’s Engine logs button. The panel
shows when logs were last collected, or No logs collected yet.
2
Collect logs
Select Collect logs. The panel shows Requested … · waiting for the
machine to check in (usually within a minute). The machine sends the end
of its Engine log files on its next check-in; for this computer it answers
within a few seconds.
3
Read the log
Each collection appears as a row — Collected … · Engine <version>
— with the files it holds and their sizes. Open a row to read the text, and
use Copy to paste it into a support conversation.
The machine sends the end of its log — up to 512 KiB of
engine.log and
128 KiB of pty-host.log — and a row shows how much of each file that is,
for example engine.log · last 512 KiB of 9.3 MiB. The last five
collections are kept per machine. Only the account that owns the machine can
request or read its logs.Stop using a server
In Your machines, select the row’s Remove button. Its credential is revoked, so it stops running work as soon as its next check-in is refused. Sign in again on that computer — or set the server up again — to add it back.Troubleshooting
Setup failures are shown in the app with a next step. The most common:
Two more general symptoms: