| name | ssh-connection-test |
| description | Test SSH connectivity to hosts configured in ~/.ssh/config using sshm. Use when diagnosing connection issues, verifying hosts are reachable, or checking all hosts after a network change. Triggers include "test ssh", "ssh connectivity", "can I connect", "ssh reachable", "sshm test". |
ssh-connection-test
Guide to testing SSH connections with sshm test.
Test a Single Host
sshm test web
Output:
testing web (deploy@example.com:22)...
ok connected (231ms)
Test All Hosts
sshm test --all
Shows a table of all hosts with connection results and timing.
Connection Result Types
| Result | Meaning |
|---|
connected | SSH handshake succeeded |
timeout | No response within 5 seconds |
refused | Port is closed |
host not found | DNS resolution failed |
auth failed | Host reachable but key rejected |
unknown error | Other SSH error |
Diagnosing Failures
timeout - Host may be down, firewall blocking port, or wrong IP. Check: ping hostname, telnet hostname 22.
refused - SSH service not running on that port. Check if port in config matches actual SSH port.
host not found - DNS issue. Try using IP address directly: sshm edit myhost --host 1.2.3.4.
auth failed - Key not accepted. Check: key exists at IdentityFile path, key is in server's authorized_keys.
How the Test Works
The test spawns ssh with:
ConnectTimeout=5 to avoid hangingBatchMode=yes to prevent interactive prompts- The host's configured user, hostname, and port
- Runs
true as the command (exits immediately on success)
The test does not create a persistent connection and does not execute any shell commands that could affect the server.
Notes
- Connection test uses the host's current config (User, HostName, Port, IdentityFile)
- Test respects IdentityFile if set
- Auth failures are distinguished from unreachable hosts
- Timing shown in milliseconds
