diff --git a/Dockerfile b/Dockerfile
index 118feb61..d7eafeac 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,6 +1,4 @@
-# Dockerfile for GNS3 server development
-
-FROM ubuntu:18.04
+FROM ubuntu:20.04
 
 ENV DEBIAN_FRONTEND noninteractive
 
@@ -12,12 +10,13 @@ ENV LC_ALL en_US.UTF-8
 RUN apt-get update && apt-get install -y software-properties-common
 RUN add-apt-repository ppa:gns3/ppa
 RUN apt-get update && apt-get install -y \
+    git \
     locales \
     python3-pip \
     python3-dev \ 
     qemu-system-x86 \
     qemu-kvm \
-    libvirt-bin \
+    libvirt-daemon-system \
     x11vnc 
 
 RUN locale-gen en_US.UTF-8
diff --git a/gns3server/endpoints/compute/__init__.py b/gns3server/endpoints/compute/__init__.py
index 045ecfeb..aaaba18a 100644
--- a/gns3server/endpoints/compute/__init__.py
+++ b/gns3server/endpoints/compute/__init__.py
@@ -14,7 +14,6 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-import asyncio
 
 from fastapi import FastAPI, Request
 from fastapi.responses import JSONResponse
@@ -112,7 +111,7 @@ async def image_missing_error_handler(request: Request, exc: ImageMissingError):
 
 
 @compute_api.exception_handler(NodeError)
-async def image_missing_error_handler(request: Request, exc: NodeError):
+async def node_error_handler(request: Request, exc: NodeError):
     return JSONResponse(
         status_code=409,
         content={"message": str(exc), "exception": exc.__class__.__name__},
@@ -120,21 +119,12 @@ async def image_missing_error_handler(request: Request, exc: NodeError):
 
 
 @compute_api.exception_handler(UbridgeError)
-async def image_missing_error_handler(request: Request, exc: UbridgeError):
+async def ubridge_error_handler(request: Request, exc: UbridgeError):
     return JSONResponse(
         status_code=409,
         content={"message": str(exc), "exception": exc.__class__.__name__},
     )
 
-
-@compute_api.exception_handler(asyncio.CancelledError)
-async def image_missing_error_handler(request: Request, exc: asyncio.CancelledError):
-    return JSONResponse(
-        status_code=408,
-        content={"message": "Request for '{}' cancelled".format(request.url.path)},
-    )
-
-
 compute_api.include_router(capabilities.router, tags=["Capabilities"])
 compute_api.include_router(compute.router, tags=["Compute"])
 compute_api.include_router(notifications.router, tags=["Notifications"])
diff --git a/gns3server/endpoints/controller/links.py b/gns3server/endpoints/controller/links.py
index 209c261a..5c6bd97a 100644
--- a/gns3server/endpoints/controller/links.py
+++ b/gns3server/endpoints/controller/links.py
@@ -148,7 +148,7 @@ async def start_capture(capture_data: dict, link: Link = Depends(dep_link)):
 
 
 @router.post("/{link_id}/stop_capture",
-             status_code=status.HTTP_201_CREATED,
+             status_code=status.HTTP_204_NO_CONTENT,
              response_model=schemas.Link,
              responses=responses)
 async def stop_capture(link: Link = Depends(dep_link)):
@@ -157,7 +157,6 @@ async def stop_capture(link: Link = Depends(dep_link)):
     """
 
     await link.stop_capture()
-    return link.__json__()
 
 
 @router.delete("/{link_id}",
@@ -201,7 +200,7 @@ async def pcap(request: Request, link: Link = Depends(dep_link)):
     headers['Router-Host'] = request.client.host
     body = await request.body()
 
-    async def compute_pcpa_stream():
+    async def compute_pcap_stream():
 
         connector = aiohttp.TCPConnector(limit=None, force_close=True)
         async with aiohttp.ClientSession(connector=connector, headers=headers) as session:
@@ -211,4 +210,4 @@ async def pcap(request: Request, link: Link = Depends(dep_link)):
                         break
                     yield data
 
-    return StreamingResponse(compute_pcpa_stream(), media_type="application/vnd.tcpdump.pcap")
+    return StreamingResponse(compute_pcap_stream(), media_type="application/vnd.tcpdump.pcap")
diff --git a/scripts/docker_dev_server.sh b/scripts/docker_dev_server.sh
index 3efef413..c358deea 100755
--- a/scripts/docker_dev_server.sh
+++ b/scripts/docker_dev_server.sh
@@ -15,9 +15,7 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-# A docker server use for localy test a remote GNS3 server  
+# A docker server use for locally test a remote GNS3 server
 
 docker build -t gns3-server .
-docker run -i -h gns3vm -p 8001:8001/tcp -t gns3-server python3 -m gns3server --port 8001
-
-
+docker run --privileged -i -h gns3vm -p 8001:8001/tcp -p 5000-5100:5000-5100 -t gns3-server python3 -m gns3server --port 8001