1. SSH hanging is not altogether uncommon, esp. on repeated reconnect over flaky connections and/or crappy-but-stateful captive portals, experienced both; also,

1. SSH hanging is not altogether uncommon, esp. on repeated reconnect over flaky connections and/or crappy-but-stateful captive portals, experienced both; also, not every SSH server is OpenSSH, esp. various embedded dropbears have been imbued with nasty device-specific quirks. 2. a simple loop might fail you unless you've remembered to use -oBatchMode=true; also it would work iff every SSH connection is terminated cleanly; also also about 20 other minor warts. Very quickly, the "simple loop" starts being decidedly unsimple, and you'll find yourself reinventing a square wheel. Been there, done that. Then I found that someone else has already been through the same issues and made a comprehensive tool for it: autossh.