Ubuntu服务器多Canvas LMS部署：第二个实例SSL协议错误求助

Hey there, let's work through why your second Canvas LMS instance is throwing that SSL protocol error. I've messed around with multi-instance Canvas setups before, so here's a step-by-step breakdown of what to check and fix:

1. Verify SSL Certificate & Key Configurations #

First off, double-check your web server (Nginx/Apache) config for the second instance. The most common issue here is misconfigured certificate paths or invalid files:

• For Nginx, ensure your server block includes correct paths to your SSL cert and key:

  ssl_certificate /path/to/valid/cert.pem;
  ssl_certificate_key /path/to/valid/private-key.pem;
  

• Confirm your certificate isn't expired by running this command:

  openssl x509 -in /path/to/your/cert.pem -text -noout | grep "Not After"
  

• If you're using a self-signed cert for local testing, make sure it's been added to your browser's trusted certificates (Chrome/Firefox often block untrusted self-signed certs with this error).

2. Check Port Listening & SSL Binding #

Since you're running instances on different ports, make sure the second instance's web server is actually listening on its assigned port with SSL enabled:

• For Nginx, your server block should explicitly listen on the port with the ssl flag:

  listen 8443 ssl; # Replace 8443 with your second instance's port
  

• Verify the port is being listened to by your web server process with:

  netstat -tulpn | grep <your-second-instance-port>
  

  You should see your web server (nginx/httpd) listed as the process using that port.

3. Fix SSL Protocol & Cipher Suite Compatibility #

Chrome's ERR_SSL_PROTOCOL_ERROR often pops up when the server uses outdated or unsupported SSL protocols. Make sure your web server config uses modern, compatible protocols:

• Add these lines to your second instance's web server config (Nginx example):

  ssl_protocols TLSv1.2 TLSv1.3;
  ssl_ciphers ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-CHACHA20-POLY1305:ECDHE-RSA-CHACHA20-POLY1305:DHE-RSA-AES128-GCM-SHA256:DHE-RSA-AES256-GCM-SHA384;
  ssl_prefer_server_ciphers off;
  

• Test the SSL connection directly with OpenSSL to spot handshake issues:

  openssl s_client -connect 192.168.0.6:<your-second-instance-port>
  

  Look for errors like "handshake failure" or "no shared cipher" in the output—these will point you to protocol/cipher problems.

4. Update Canvas LMS Internal Configs #

Canvas itself might be misconfigured to use SSL correctly for the second instance:

• Navigate to your second instance's config directory (/var/directoryname/canvas/config) and check domain.yml:

  production:
    domain: '192.168.0.6:<your-second-instance-port>'
    ssl: true
  

• Recompile assets to ensure static resources use the correct HTTPS URL:

  cd /var/directoryname/canvas
  bundle exec rake assets:precompile RAILS_ENV=production
  

• Restart your Canvas application server (Puma/Unicorn) to apply config changes.

5. Check Firewall & Network Access #

Don't overlook basic network issues:

• Ensure your server's firewall (ufw/iptables) allows incoming traffic on the second instance's port:

  ufw allow <your-second-instance-port>/tcp
  

• If testing from your local machine, confirm you can ping the server (ping 192.168.0.6) and that there are no router/firewall rules blocking the port between your computer and the server.

Quick Sanity Check: Test HTTP First #

If all else fails, temporarily disable SSL for the second instance (switch web server config to listen on HTTP) and test if you can access it. If HTTP works, the problem is definitely isolated to SSL configuration. If HTTP also fails, you'll need to troubleshoot your web server's basic setup or Canvas instance startup first.

I've hit most of these issues myself when setting up multiple Canvas instances—start with the certificate and port configs, those are the usual culprits!

内容的提问来源于stack exchange，提问作者Anup Kumar Mondal