OS Template Download Stuck or Failed

OS template downloads are designed to fail safely: Virtlix downloads to a temporary file first and only marks a template as cached once the download completes successfully (and passes a checksum check, when one is configured) - so a template that shows as "Not downloaded" after a failed attempt genuinely never has a half-written, corrupt image sitting around waiting to break a future VPS build.

If a download shows 0% progress and never advances: check the node actually has outbound internet access to the source URL - curl -I <the template's source URL> from the host itself should return a real HTTP response. A firewalled or offline node will just sit at 0% indefinitely with no other symptom.

If a download fails immediately with a checksum error: the source file changed since the checksum was recorded (common for templates using a distro's "latest" rolling alias, which does legitimately update over time) - this isn't a corrupted download, it's a stale checksum. Re-syncing the OS template catalog from the master (OS Templates → Add/Download Templates → Sync from master) refreshes template metadata including current checksums.

If a download appears to hang partway through on a node with multiple concurrent queue workers: check whether the exact same template was queued for download twice at nearly the same time - a duplicate concurrent download of the same file is locked out safely rather than corrupting the file, so the second click's job simply no-ops rather than actually re-downloading; the first one already in progress is the real one to watch.

Whatever the cause, /var/log/virtlix-install.log and the queue worker's own logs show the actual wget/curl error for that specific download attempt, which is almost always more specific than what the panel's progress bar alone can show.