1) install tmate
apt-get install tmate
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brew update && \
brew tap nviennot/tmate && \
brew install tmate
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yum install tmate
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2) use tmate.ip.fi, instead of default server
curl http://tmate.ip.fi/tmate.conf | tee ~/.tmate.conf

3) get SSH url to share
tmate
tmate show-messages

4) provide RO or RW URL to far end and rock on