When a Docker container with the same name already exists (e.g., from a
previous crashed GNS3 session), Docker returns a 409 Conflict error
when trying to create a new container with that name. This causes the
project open operation to fail.
This fix adds automatic cleanup of stale containers when encountering
a name conflict:
- Added DockerHttp409Error exception class
- Updated http_query to detect 409 status codes
- Modified create() to remove conflicting containers and retry
Fixes the issue where opening a project fails with:
"Docker has returned an error: 409 Conflict. The container name
'/GNS3.xxx' is already in use by container 'xxx'"
Rootful Docker recreates volume mount points as root on start,
preventing the GNS3 process from writing files into node directories
while the container is running. self._fix_permissions() would resolve
this but is currently only called at container stop time.
- _fix_permissions: capture stderr, check returncode, only set
_permissions_fixed on success instead of silently marking as fixed
- list_node_files: wrap os.scandir in try-except to handle
PermissionError gracefully
When updating project variables while Docker containers are running, the
system now properly handles both dictionary-format variables and Pydantic
Variable objects. This prevents AttributeError when containers are recreated
after variable updates.
Changes:
- Modified DockerVM.create() to detect and handle Pydantic Variable objects
- Updated _format_env() method to support both variable formats
- Maintains backward compatibility with existing dictionary format
Fixes error: AttributeError: 'Variable' object has no attribute 'get'
When closing a Docker node, if container deletion fails, the error
is silently ignored. This can lead to stale containers remaining on
the system and causing 409 conflicts when reopening projects.
Changes:
- Distinguish between 404 (container already removed, normal) and
other DockerError (deletion failed, needs attention)
- Log warning when deletion fails with error details
- Add comment explaining stale containers will be cleaned up on
project open (via automatic 409 conflict resolution)
This improves observability without blocking project close operations.
The root cause of stale containers can now be diagnosed from logs.
Fixes#2708
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
When a hostname validation fails, the error message now includes
the allowed character set to help users provide valid names.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
When a Docker container with the same name already exists (e.g., from a
previous crashed GNS3 session), Docker returns a 409 Conflict error
when trying to create a new container with that name. This causes the
project open operation to fail.
This fix adds automatic cleanup of stale containers when encountering
a name conflict:
- Added DockerHttp409Error exception class
- Updated http_query to detect 409 status codes
- Modified create() to remove conflicting containers and retry
Fixes the issue where opening a project fails with:
"Docker has returned an error: 409 Conflict. The container name
'/GNS3.xxx' is already in use by container 'xxx'"
Most VNC clients use the Desktop name in their window title.
Currently this defaults to user@host which means all docker vnc
connections have identical window names of e.g.
SSVNC: gns3@gns3server
This uses the node name instead.