Troubleshooting Common Issues in Ewe Virtual Machine
1. VM won’t start
- Check status: Run the VM manager’s status command (e.g., ewectl status) to see boot logs.
- Disk space: Ensure host has free disk and inode space (
df -h,df -i). - Corrupt image: Verify image checksums and replace or re-import if corrupted.
- Kernel/boot errors: Inspect serial/console logs (
journalctl -kor VM console) for kernel oops or init failures.
2. Network connectivity problems
- Interface up: Confirm VM network interface is up inside the guest (
ip addr,ip link). - DHCP vs static: Verify DHCP lease or static IP settings; check /etc/netplan or network config used by Ewe.
- Host forwarding: Ensure host bridge/NAT and firewall rules allow traffic (iptables/nft, firewalld).
- DNS: Test with IP (ping 8.8.8.8) then DNS (ping example.com); fix /etc/resolv.conf or DNS service.
3. Slow performance or high latency
- Resource saturation: Check CPU, memory, disk I/O on host and guest (
top,htop,iostat,vmstat). - Overcommitment: Reduce host overcommit or increase VM vCPU/RAM.
- Storage latency: Inspect disk latency and consider switching to faster storage or enabling caching modes.
- Virtio drivers: Ensure latest paravirtual drivers are installed in the guest for network and disk.
4. Disk full or I/O errors
- Filesystem usage: Identify large files (
du -sh /*), clear logs, or expand disk image. - Filesystem corruption: Run fsck on unmounted partitions or boot into recovery to repair.
- Quota or LVM issues: Check LVM status, logical volume sizes, and quotas.
5. VM crashes or kernel panics
- Crash logs: Collect dmesg, journalctl, and host hypervisor logs.
- OOM kills: Look for OOM killer messages; increase memory or tune application limits.
- Hardware/driver bugs: Update guest kernel and hypervisor tools; check known bugtracker entries.
6. Unable to SSH into VM
- SSH service: Confirm sshd is running (
systemctl status sshd) and listening (ss -tnlp | grep :22). - Firewall: Check guest and host firewall rules.
- Key/auth issues: Verify authorized_keys permissions and SSH server config (PermitRootLogin, PubkeyAuthentication).
- Network path: Validate routing and NAT/port-forward rules on host.
7. Time drift between host and guest
- NTP/chrony: Ensure guest runs NTP client or chrony and syncs to reliable servers.
- Hypervisor sync: Enable host-guest time synchronization if supported.
8. Snapshot and backup failures
- Consistency: Quiesce the filesystem or use guest agents for consistent snapshots.
- Space and locks: Ensure sufficient space for snapshots and no stale snapshot locks.
- Agent availability: Verify backup/snapshot agent is reachable and has correct permissions.
9. Licensing or activation errors (if applicable)
- Clock and IDs: Ensure VM clock and machine IDs are correct for license checks.
- Network access: Confirm licensing servers are reachable and not blocked by firewall.
10. Logs and debugging checklist (what to collect)
- Host hypervisor logs (ewe host logs)
- VM serial/console output
- Guest system logs: /var/log/syslog, journalctl, dmesg
- Network captures (tcpdump) for connectivity issues
- Resource metrics: top/htop, iostat, vmstat
If you want, I can generate a tailored troubleshooting checklist or command snippets for your environment (Linux guest, specific hypervisor, etc.).
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