Responding to modumb,
Sorry to others, has no relation to the title of the post
I had to use extroot on my AR750 Creta. Only free150kb after installing 3.201beta2. 0227 firmware and it was impossible to install anything else.
I had al old 512Mb USB Pendrive and it’s very easy to make it as dev/sdb1 >>/overlay in Luci>System>Mount Points, I’n not an expert in OpenWRT and also no trouble with UI so far.
But I had to make extroot right after fresh clean firmware update and no internet at all to maintain those 150Kb free in AR750. After that I made restore and I install the .ipk plugins I had previously.
Be sure to reboot after extroot and see the sdb1 /overlay working or in Luci>System>Software the increased free space of your USB or SD Card (SD Card maybe is named /sda1)
I do not have preferences, but I can suggest some popular Linux software that can be used for SSH connections to GL routers:
OpenSSH: OpenSSH is a widely used and well-documented open-source software suite that provides secure network communication via the SSH protocol. OpenSSH is included with most Linux distributions and can be used to connect to GL routers over SSH.
PuTTY: PuTTY is a free and open-source terminal emulator, serial console, and network file transfer application that supports SSH and other protocols. It is available for Windows and Linux and can be used to connect to GL routers over SSH.
Termius: Termius is a popular cross-platform SSH client that supports SSH, Mosh, and Telnet protocols. It provides a modern terminal emulator with advanced features such as multi-tabs, search, and terminal sessions syncing.
SecureCRT: SecureCRT is a commercial SSH client that provides advanced terminal emulation capabilities, including support for multiple sessions, tabs, and custom keymaps. It is available for Windows, macOS, and Linux and can be used to connect to GL routers over SSH.
MobaXterm: MobaXterm is a comprehensive terminal emulator for Windows that provides support for SSH, Telnet, RDP, VNC, X11, and more. It includes advanced features such as multi-tabs, a file browser, and an embedded X server.
PuTTY because it has been around forever, is free and simple to use for what I want to do; and has a cool name.
iTerminal (Pro) on my iPAD/iPhone. Helps me troubleshoot on the go or Wifi/VPN connections from my mobile device, that go through the GLiNET Router.
WinSCP (not strictly SSH) because it is useful for transferring (backing up) DHCP Reservation files, especially those that I save from nvram on my ASUS RT-AX86U Router. Super useful when you have about 40+ such reservations (with custom icons and reservation names) to re-upload after a major (Asus Merlin) firmware update. Also used on my GLiNET router to edit a file (in /etc/config/wireless) for the Wifi (changed the Country Code as described here).