无法连接Google Cloud Engine：SSH连接重置及网页端无限等待问题

Looks like your GCE instance was working fine yesterday but now throwing that ssh_exchange_identification: read: Connection reset by peer error (with gcloud returning code 255) and the web SSH is stuck loading. Let’s break down the fixes step by step:

1. Verify Instance Health & Basic Status #

• First, check if your instance is in the RUNNING state in the Google Cloud Console. Sometimes instances get restarted or rescheduled automatically, which can temporarily disrupt connections.
• Check the Serial Port Output for your instance (under the "Serial port" tab in the Console). Look for errors related to the sshd service failing to start—this could point to boot-time issues preventing SSH from initializing.

2. Check Firewall & Network Configurations #

• Confirm your SSH firewall rule is active: The default allow-ssh rule should allow incoming traffic on port 22 from your IP address (or a trusted range). Double-check that the rule applies to your instance’s network tags (if using tag-based rules) and that your instance has those tags assigned.
• Ensure there’s no recent VPC peering or route change that’s blocking SSH traffic to your instance. If you modified network routes lately, revert them temporarily to test.

3. Diagnose SSH Service on the Instance #

If you have serial console access enabled (you can toggle this in the instance settings if not):

• Log in via the serial console and run sudo systemctl status sshd to check if the SSH daemon is running. If it’s stopped, start it with sudo systemctl start sshd and enable auto-start with sudo systemctl enable sshd.
• Validate the SSH config file with sshd -t—this will catch syntax errors in /etc/ssh/sshd_config that might be breaking the service (like invalid permissions, disabled authentication methods, or a non-standard port without proper firewall access).

4. Fix Local & gcloud Tool Issues #

• Update your gcloud SDK to the latest version: Run gcloud components update to eliminate compatibility bugs with newer GCE features.
• Clear stale SSH host entries: Execute ssh-keygen -R <INSTANCE_PUBLIC_IP> to remove old cached host keys that might be causing connection conflicts.
• Run gcloud in debug mode for more details: gcloud compute ssh YOUR_INSTANCE_NAME --zone YOUR_ZONE --verbosity debug—the verbose logs will show exactly where the connection is failing (e.g., network handshake, authentication).

5. Check for Google Cloud Infrastructure Outages #

Sometimes the issue isn’t on your end—verify if your GCE region is experiencing any service disruptions by checking Google Cloud’s status page. Regional outages can cause SSH connections to reset or hang indefinitely.

Last Resort: Reset the Instance #

If all else fails, try resetting your instance from the Console. This will reboot the system, which often resolves temporary network stack deadlocks or boot-time glitches. Note that running processes will be terminated, but your persistent disk data will remain intact.

内容的提问来源于stack exchange，提问作者Evgeniya Tveritinova