SSH / SFTP / Mosh / rz/sz

SSH resources can be opened as a terminal, an SFTP file manager, or a Mosh session.

Basic Configuration

Field	Description
Name	Resource display name
Host	SSH server address
TCP Port	SSH port, default 22
UDP Port	Mosh data port. Leave empty or 0 to auto-assign (recommended), or specify a fixed port (Mosh only)
Username	SSH username
Authentication Method	Enter each time, saved password, or private key

Authentication Methods

Enter Each Time

A password input dialog appears when opening the resource. Suitable for scenarios where you don't want to save the password.

Saved Password

The password is saved in the resource configuration. Suitable for low-risk internal network services.

Private Key

First, add a private key in Settings > Resources > SSH, then select that key in the SSH resource.

Private keys can be added in two ways:

• Paste an existing private key.
• Generate a new Ed25519 private key.

If the private key has a passphrase and the passphrase is not saved in settings, you will be prompted to enter it when connecting.

SSH Terminal

The terminal supports:

• Theme configuration.
• Font size configuration.
• Pinch-to-zoom for font size.
• Quick input bar.
• Ctrl / Alt sticky keys.
• Arrow keys, PageUp, PageDown, Home, End.
• F1 through F12.

When running on macOS, the mobile quick input bar is typically hidden because a physical keyboard is more suitable for terminal input.

Selection and Copy

iOS / iPadOS

• Long-press terminal text to open the context menu, then choose "Select" to select a word or "Select All" for the entire buffer.
• Drag to extend the selection.
• Use "Copy" and "Paste" from the context menu.
• Tap elsewhere to cancel the selection.

macOS

• Drag with the mouse or trackpad to select text directly.
• Double-click to select a word.
• Click elsewhere to cancel the selection.
• ⌘C copies the selection; ⌘V pastes.

Ctrl and Alt Sticky Keys

Tapping Ctrl or Alt puts them into a held state. Pressing another key sends a key combination, for example:

• Tapping Ctrl then C is equivalent to Ctrl+C.
• Tapping Alt then an arrow key can trigger combined actions in terminal programs.

After sending a key combination, the sticky state is automatically released.

SFTP Mode

Choose SFTP from the SSH / SFTP / Mosh selector on the SSH resource edit page. The resource will then appear as SFTP in the resource list and open the file management interface.

Mosh Mode

Choose Mosh from the SSH / SFTP / Mosh selector to use the original Mosh 1.4 terminal protocol.

Connection sequence:

1. OmniGate connects to the target host through the configured TCP SSH port.
2. SSH authentication starts mosh-server on the remote host.
3. The terminal switches to the allocated or specified UDP port for the Mosh session.

UDP Port Configuration:

• Auto-assign (Recommended): Leave empty or set to 0. The server dynamically allocates an available UDP port within its range (typically 60000–61000). This prevents port collisions and allows opening multiple concurrent Mosh sessions.
• Fixed Port: Enter a specific port (e.g. 60000). Suitable for strict firewall environments or port-forwarding setups (ensure the remote firewall allows this UDP port).

Port Conflict Resolution & Session Termination:

• When using a fixed port that is already in use (e.g. an orphaned mosh-server daemon still listening after a disconnect, resulting in Address already in use), the app prompts you with an option to "Terminate Old Session & Reconnect".
• You can also enable "Auto-terminate old session on port conflict" in the resource settings to automatically displace stale processes on that port without prompting.

Requirements:

• The remote host must have mosh-server installed.
• UDP packets from OmniGate to the target host must be allowed.
• Mosh is available with all gateway types except FRP.

Mosh uses the same username, password, and private-key configuration as SSH. It is designed for unstable or roaming networks and can resynchronize after short interruptions or address changes.

Mosh resources do not provide SFTP or rz/sz transfer in the same resource. Create a separate SSH or SFTP resource if both a terminal and file transfer are needed.

SFTP default directory policy:

• Username is root: defaults to /
• Other usernames: defaults to /home/<username>
• If a default directory is manually specified, the manual value is used.

rz/sz File Transfer

When SSH mode is selected, you can enable rz/sz file transfer. This is suitable for SSH jump server scenarios because it transmits through the terminal session and does not rely on a separate SFTP channel.

Usage:

• After running rz on the remote side, the app shows a file picker for upload.
• After running sz <file> on the remote side, the app receives and saves the file.

Notes:

• rz/sz requires lrzsz or a compatible tool to be installed on the remote side.
• Do not close the SSH page during transfer.
• If the terminal prints abnormal control characters, it may be due to the remote shell, terminal program, or zmodem tool output mixing with the protocol stream.