I was fronted with this problem today. I upgraded ruby on my clients UAT last week and ruby-openssl modules wasn’t installed due to missing header files. I recon this would only happen if you install ruby from source. However without openssl build-in, the net/ssh will fail most of the time. But you can easily install this manually.
1. Navigate to ext/openssl in the ruby source folder and do the following.
ruby extconf.rb
make
make install
NOTE: make sure you have openssl and openssl-devel packages installed in your system first. Otherwise you will get an error like this. (This is based on a Redhat based distribution)
=== OpenSSL for Ruby configurator ===
=== Checking for system dependent stuff… ===
checking for t_open() in -lnsl… no
checking for socket() in -lsocket… no
checking for assert.h… yes
=== Checking for required stuff… ===
checking for openssl/ssl.h… no
=== Checking for required stuff failed. ===
Makefile wasn’t created. Fix the errors above.
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