There seems to be no lego binary in
/opt/bitnami/letsencrypt/. You can download it with the following commands:
curl -Ls https://api.github.com/repos/xenolf/lego/releases/latest | grep browser_download_url | grep linux_amd64 | cut -d '"' -f 4 | wget -i -
tar xf lego_v2.4.0_linux_amd64.tar.gz
sudo mv lego /opt/bitnami/letsencrypt/lego
After that try to run the
generate-certificate.sh script again.
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