Hi, I have a problem. Actually, every time I try to access a device via SSH or even through the console port using screen, it doesn’t work. I get error messages. Here’s an example:
#Not Working SSH
vivid wigeon
sullen oracleBOT
Hi @vivid wigeon. I'm kapa.ai, your friendly support bot. I will try to answer your question by searching through the knowledge base. :wave:
It sounds like Warp’s SSH wrapper is interfering with your connections. Warp “wraps” ssh to enable features (blocks, prompt, completions), but this can fail with certain devices, shells, or environments (e.g., network gear, WP Engine sidecar, Windows OpenSSH, fish, non-POSIX shells). Common symptoms include syntax errors, “exec” errors, channel open failures, or immediate disconnects. Here are proven workarounds:
-
Bypass Warp’s SSH wrapper for a single command:
- Run:
command ssh user@host(this uses the system ssh and avoids Warp’s wrapper) (SSH legacy docs). - Several users report this eliminates errors like “channel n: open failed” and various syntax issues with devices and services such as WP Engine and network switches (SSH errors WPEngine, Channel open failed workaround).
- Run:
-
Disable the SSH wrapper globally:
- Settings > Features > turn off “Warp SSH Wrapper.” This restores normal SSH (but disables Warp blocks on remote) (SSH legacy docs, FortiGate thread, OpenVMS thread).
-
Per-session env toggle:
- Set
WARP_USE_SSH_WRAPPER=0before ssh, useful for problematic hosts (reported by users connecting to older switches) (SSH fails for specific host).
- Set
-
If connecting to Windows hosts:
- Warp’s wrapper doesn’t work with PowerShell/Windows OpenSSH; install Cygwin ssh on the remote or bypass the wrapper (
command ssh) (Windows SSH issue, SSH legacy docs).
- Warp’s wrapper doesn’t work with PowerShell/Windows OpenSSH; install Cygwin ssh on the remote or bypass the wrapper (
-
If the remote default shell is fish or non-bash/zsh:
- The wrapper only supports bash and zsh; switch the remote shell to bash/zsh or bypass the wrapper (SSH legacy docs, fish error).
-
If you see “channel n: open failed” spam:
- Try
command sshto bypass the wrapper, or raise MaxSessions on the server; Warp uses ControlMaster for features (SSH legacy docs, channel errors workaround).
- Try
-
On macOS 15 “No route to host” in Warp only:
- Ensure Warp has Local Network permission: System Settings > Privacy & Security > Local Network (No route to host).
About console via screen: I don’t see specific docs/issues about screen in the sources. If screen is failing similarly, it might be unrelated to the SSH wrapper. I’m sorry, but there’s no information about Warp affecting screen in the provided knowledge.