diff mbox series

[ovs-dev,v4] ovs-tcpdump: Cleanup mirror port on SIGHUP/SIGTERM

Message ID 20220908073726.1232-1-zhihui.ding@easystack.cn
State Changes Requested
Headers show
Series [ovs-dev,v4] ovs-tcpdump: Cleanup mirror port on SIGHUP/SIGTERM | expand

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Commit Message

Daniel Ding Sept. 8, 2022, 7:37 a.m. UTC 
If ovs-tcpdump received HUP or TERM signal, mirror and mirror
interface should be destroyed. This often happens, when
controlling terminal is closed, like ssh session closed, and
other users use kill to terminate it.

Acked-by: Mike Pattrick <mkp@redhat.com>
Signed-off-by: Daniel Ding <zhihui.ding@easystack.cn>
---
 utilities/ovs-tcpdump.in | 27 +++++++++++++++------------
 1 file changed, 15 insertions(+), 12 deletions(-)

Comments

Ilya Maximets Sept. 9, 2022, 5:43 p.m. UTC | #1 
On 9/8/22 09:37, Daniel Ding wrote:
> If ovs-tcpdump received HUP or TERM signal, mirror and mirror
> interface should be destroyed. This often happens, when
> controlling terminal is closed, like ssh session closed, and
> other users use kill to terminate it.
> 
> Acked-by: Mike Pattrick <mkp@redhat.com>
> Signed-off-by: Daniel Ding <zhihui.ding@easystack.cn>
> ---
>  utilities/ovs-tcpdump.in | 27 +++++++++++++++------------
>  1 file changed, 15 insertions(+), 12 deletions(-)
> 
> diff --git a/utilities/ovs-tcpdump.in b/utilities/ovs-tcpdump.in
> index 7fd26e405..b3f764c87 100755
> --- a/utilities/ovs-tcpdump.in
> +++ b/utilities/ovs-tcpdump.in
> @@ -44,6 +44,7 @@ try:
>      from ovs import jsonrpc
>      from ovs.poller import Poller
>      from ovs.stream import Stream
> +    from ovs.fatal_signal import add_hook
>  except Exception:
>      print("ERROR: Please install the correct Open vSwitch python support")
>      print("       libraries (version @VERSION@).")
> @@ -405,6 +406,17 @@ def py_which(executable):
>                 for path in os.environ["PATH"].split(os.pathsep))
>  
>  
> +def teardown(db_sock, interface, mirror_interface, tap_created):
> +    def cleanup_mirror():
> +        ovsdb = OVSDB(db_sock)
> +        ovsdb.destroy_mirror(interface, ovsdb.port_bridge(interface))
> +        ovsdb.destroy_port(mirror_interface, ovsdb.port_bridge(interface))
> +        if tap_created is True:
> +            _del_taps[sys.platform](mirror_interface)
> +
> +    add_hook(cleanup_mirror, None, True)
> +
> +
>  def main():
>      rundir = os.environ.get('OVS_RUNDIR', '@RUNDIR@')
>      db_sock = 'unix:%s' % os.path.join(rundir, "db.sock")
> @@ -489,6 +501,9 @@ def main():
>          print("ERROR: Mirror port (%s) exists for port %s." %
>                (mirror_interface, interface))
>          sys.exit(1)
> +
> +    teardown(db_sock, interface, mirror_interface, tap_created)
> +
>      try:
>          ovsdb.make_port(mirror_interface, ovsdb.port_bridge(interface))
>          ovsdb.bridge_mirror(interface, mirror_interface,
> @@ -496,12 +511,6 @@ def main():
>                              mirror_select_all)
>      except OVSDBException as oe:
>          print("ERROR: Unable to properly setup the mirror: %s." % str(oe))
> -        try:
> -            ovsdb.destroy_port(mirror_interface, ovsdb.port_bridge(interface))
> -            if tap_created is True:
> -                _del_taps[sys.platform](mirror_interface)
> -        except Exception:
> -            pass
>          sys.exit(1)
>  
>      ovsdb.close_idl()
> @@ -517,12 +526,6 @@ def main():
>      except KeyboardInterrupt:
>          if pipes.poll() is None:
>              pipes.terminate()
> -
> -        ovsdb = OVSDB(db_sock)
> -        ovsdb.destroy_mirror(interface, ovsdb.port_bridge(interface))
> -        ovsdb.destroy_port(mirror_interface, ovsdb.port_bridge(interface))
> -        if tap_created is True:
> -            _del_taps[sys.platform](mirror_interface)
>      except Exception:
>          print("Unable to tear down the ports and mirrors.")
>          print("Please use ovs-vsctl to remove the ports and mirrors created.")

I think there was some misunderstanding here.  Sorry about that.
What I meant is that cleanup_mirror() function should have a
try-except block and have the 'print's above in the 'except' section.

i.e.

def teardown(...):
    def cleanup_mirror():
        try:
            <destroy a mirror>
        except Exception:
            print("Unable to tear down the ports and mirrors.")
            print("Please use ovs-vsctl to remove the ports and mirrors created.")
            print(" ex: ovs-vsctl --db=...

    add_hook(cleanup_mirror, None, True)

And for the pipes.poll() loop we only need to catch the KeyboardInterrupt.
No need to catch generic exceptions, IIUC.  The hook will be executed
anyway, even on the unexpected exception, right?

Best regards, Ilya Maximets.
Daniel Ding Sept. 12, 2022, 1:55 p.m. UTC | #2 
On 2022/9/10 1:43, Ilya Maximets wrote:
> On 9/8/22 09:37, Daniel Ding wrote:
>> If ovs-tcpdump received HUP or TERM signal, mirror and mirror
>> interface should be destroyed. This often happens, when
>> controlling terminal is closed, like ssh session closed, and
>> other users use kill to terminate it.
>>
>> Acked-by: Mike Pattrick<mkp@redhat.com>
>> Signed-off-by: Daniel Ding<zhihui.ding@easystack.cn>
>> ---
>>   utilities/ovs-tcpdump.in | 27 +++++++++++++++------------
>>   1 file changed, 15 insertions(+), 12 deletions(-)
>>
>> diff --git a/utilities/ovs-tcpdump.in b/utilities/ovs-tcpdump.in
>> index 7fd26e405..b3f764c87 100755
>> --- a/utilities/ovs-tcpdump.in
>> +++ b/utilities/ovs-tcpdump.in
>> @@ -44,6 +44,7 @@ try:
>>       from ovs import jsonrpc
>>       from ovs.poller import Poller
>>       from ovs.stream import Stream
>> +    from ovs.fatal_signal import add_hook
>>   except Exception:
>>       print("ERROR: Please install the correct Open vSwitch python support")
>>       print("       libraries (version @VERSION@).")
>> @@ -405,6 +406,17 @@ def py_which(executable):
>>                  for path in os.environ["PATH"].split(os.pathsep))
>>   
>>   
>> +def teardown(db_sock, interface, mirror_interface, tap_created):
>> +    def cleanup_mirror():
>> +        ovsdb = OVSDB(db_sock)
>> +        ovsdb.destroy_mirror(interface, ovsdb.port_bridge(interface))
>> +        ovsdb.destroy_port(mirror_interface, ovsdb.port_bridge(interface))
>> +        if tap_created is True:
>> +            _del_taps[sys.platform](mirror_interface)
>> +
>> +    add_hook(cleanup_mirror, None, True)
>> +
>> +
>>   def main():
>>       rundir = os.environ.get('OVS_RUNDIR', '@RUNDIR@')
>>       db_sock = 'unix:%s' % os.path.join(rundir, "db.sock")
>> @@ -489,6 +501,9 @@ def main():
>>           print("ERROR: Mirror port (%s) exists for port %s." %
>>                 (mirror_interface, interface))
>>           sys.exit(1)
>> +
>> +    teardown(db_sock, interface, mirror_interface, tap_created)
>> +
>>       try:
>>           ovsdb.make_port(mirror_interface, ovsdb.port_bridge(interface))
>>           ovsdb.bridge_mirror(interface, mirror_interface,
>> @@ -496,12 +511,6 @@ def main():
>>                               mirror_select_all)
>>       except OVSDBException as oe:
>>           print("ERROR: Unable to properly setup the mirror: %s." % str(oe))
>> -        try:
>> -            ovsdb.destroy_port(mirror_interface, ovsdb.port_bridge(interface))
>> -            if tap_created is True:
>> -                _del_taps[sys.platform](mirror_interface)
>> -        except Exception:
>> -            pass
>>           sys.exit(1)
>>   
>>       ovsdb.close_idl()
>> @@ -517,12 +526,6 @@ def main():
>>       except KeyboardInterrupt:
>>           if pipes.poll() is None:
>>               pipes.terminate()
>> -
>> -        ovsdb = OVSDB(db_sock)
>> -        ovsdb.destroy_mirror(interface, ovsdb.port_bridge(interface))
>> -        ovsdb.destroy_port(mirror_interface, ovsdb.port_bridge(interface))
>> -        if tap_created is True:
>> -            _del_taps[sys.platform](mirror_interface)
>>       except Exception:
>>           print("Unable to tear down the ports and mirrors.")
>>           print("Please use ovs-vsctl to remove the ports and mirrors created.")
The above 'except' section, should be remove it, if I understand correctlly.
> I think there was some misunderstanding here.  Sorry about that.
> What I meant is that cleanup_mirror() function should have a
> try-except block and have the 'print's above in the 'except' section.
>
> i.e.
>
> def teardown(...):
>      def cleanup_mirror():
>          try:
>              <destroy a mirror>
>          except Exception:
>              print("Unable to tear down the ports and mirrors.")
>              print("Please use ovs-vsctl to remove the ports and mirrors created.")
>              print(" ex: ovs-vsctl --db=...
>
>      add_hook(cleanup_mirror, None, True)

Okay, I will add try-except block in cleanup_mirror() function again, 
and prints
warning.
>
> And for the pipes.poll() loop we only need to catch the KeyboardInterrupt.
> No need to catch generic exceptions, IIUC.  The hook will be executed
> anyway, even on the unexpected exception, right?

Right. The third parameter of add_hook indicats the hook function need 
be run
at exiting even on the unexpeted exception.
>
> Best regards, Ilya Maximets.
>

Thanks for your review, @Ilya Maximets. And the following is newer patch
according to your suggestions.


---
  utilities/ovs-tcpdump.in | 40 ++++++++++++++++++++++------------------
  1 file changed, 22 insertions(+), 18 deletions(-)

diff --git a/utilities/ovs-tcpdump.in b/utilities/ovs-tcpdump.in
index 7fd26e405..92cff6d2c 100755
--- a/utilities/ovs-tcpdump.in
+++ b/utilities/ovs-tcpdump.in
@@ -44,6 +44,7 @@ try:
      from ovs import jsonrpc
      from ovs.poller import Poller
      from ovs.stream import Stream
+    from ovs.fatal_signal import add_hook
  except Exception:
      print("ERROR: Please install the correct Open vSwitch python support")
      print("       libraries (version @VERSION@).")
@@ -405,6 +406,24 @@ def py_which(executable):
                 for path in os.environ["PATH"].split(os.pathsep))


+def teardown(db_sock, interface, mirror_interface, tap_created):
+    def cleanup_mirror():
+        try:
+            ovsdb = OVSDB(db_sock)
+            ovsdb.destroy_mirror(interface, ovsdb.port_bridge(interface))
+            ovsdb.destroy_port(mirror_interface, 
ovsdb.port_bridge(interface))
+            if tap_created is True:
+                _del_taps[sys.platform](mirror_interface)
+        except Exception:
+            print("Unable to tear down the ports and mirrors.")
+            print("Please use ovs-vsctl to remove the ports and mirrors"
+                  " created.")
+            print(" ex: ovs-vsctl --db=%s del-port %s" % (db_sock,
+ mirror_interface))
+
+    add_hook(cleanup_mirror, None, True)
+
+
  def main():
      rundir = os.environ.get('OVS_RUNDIR', '@RUNDIR@')
      db_sock = 'unix:%s' % os.path.join(rundir, "db.sock")
@@ -489,6 +508,9 @@ def main():
          print("ERROR: Mirror port (%s) exists for port %s." %
                (mirror_interface, interface))
          sys.exit(1)
+
+    teardown(db_sock, interface, mirror_interface, tap_created)
+
      try:
          ovsdb.make_port(mirror_interface, ovsdb.port_bridge(interface))
          ovsdb.bridge_mirror(interface, mirror_interface,
@@ -496,12 +518,6 @@ def main():
                              mirror_select_all)
      except OVSDBException as oe:
          print("ERROR: Unable to properly setup the mirror: %s." % str(oe))
-        try:
-            ovsdb.destroy_port(mirror_interface, 
ovsdb.port_bridge(interface))
-            if tap_created is True:
-                _del_taps[sys.platform](mirror_interface)
-        except Exception:
-            pass
          sys.exit(1)

      ovsdb.close_idl()
@@ -518,18 +534,6 @@ def main():
          if pipes.poll() is None:
              pipes.terminate()

-        ovsdb = OVSDB(db_sock)
-        ovsdb.destroy_mirror(interface, ovsdb.port_bridge(interface))
-        ovsdb.destroy_port(mirror_interface, ovsdb.port_bridge(interface))
-        if tap_created is True:
-            _del_taps[sys.platform](mirror_interface)
-    except Exception:
-        print("Unable to tear down the ports and mirrors.")
-        print("Please use ovs-vsctl to remove the ports and mirrors 
created.")
-        print(" ex: ovs-vsctl --db=%s del-port %s" % (db_sock,
- mirror_interface))
-        sys.exit(1)
-
      sys.exit(0)



Best regards, Daniel Ding.
Aaron Conole Sept. 13, 2022, 2:30 p.m. UTC | #3 
Daniel Ding <zhihui.ding@easystack.cn> writes:

> On 2022/9/10 1:43, Ilya Maximets wrote:
>
>  On 9/8/22 09:37, Daniel Ding wrote:
>
>  If ovs-tcpdump received HUP or TERM signal, mirror and mirror
> interface should be destroyed. This often happens, when
> controlling terminal is closed, like ssh session closed, and
> other users use kill to terminate it.
>
> Acked-by: Mike Pattrick <mkp@redhat.com>
> Signed-off-by: Daniel Ding <zhihui.ding@easystack.cn>
> ---
>  utilities/ovs-tcpdump.in | 27 +++++++++++++++------------
>  1 file changed, 15 insertions(+), 12 deletions(-)
>
> diff --git a/utilities/ovs-tcpdump.in b/utilities/ovs-tcpdump.in
> index 7fd26e405..b3f764c87 100755
> --- a/utilities/ovs-tcpdump.in
> +++ b/utilities/ovs-tcpdump.in
> @@ -44,6 +44,7 @@ try:
>      from ovs import jsonrpc
>      from ovs.poller import Poller
>      from ovs.stream import Stream
> +    from ovs.fatal_signal import add_hook
>  except Exception:
>      print("ERROR: Please install the correct Open vSwitch python support")
>      print("       libraries (version @VERSION@).")
> @@ -405,6 +406,17 @@ def py_which(executable):
>                 for path in os.environ["PATH"].split(os.pathsep))
>  
>  
> +def teardown(db_sock, interface, mirror_interface, tap_created):
> +    def cleanup_mirror():
> +        ovsdb = OVSDB(db_sock)
> +        ovsdb.destroy_mirror(interface, ovsdb.port_bridge(interface))
> +        ovsdb.destroy_port(mirror_interface, ovsdb.port_bridge(interface))
> +        if tap_created is True:
> +            _del_taps[sys.platform](mirror_interface)
> +
> +    add_hook(cleanup_mirror, None, True)
> +
> +
>  def main():
>      rundir = os.environ.get('OVS_RUNDIR', '@RUNDIR@')
>      db_sock = 'unix:%s' % os.path.join(rundir, "db.sock")
> @@ -489,6 +501,9 @@ def main():
>          print("ERROR: Mirror port (%s) exists for port %s." %
>                (mirror_interface, interface))
>          sys.exit(1)
> +
> +    teardown(db_sock, interface, mirror_interface, tap_created)
> +
>      try:
>          ovsdb.make_port(mirror_interface, ovsdb.port_bridge(interface))
>          ovsdb.bridge_mirror(interface, mirror_interface,
> @@ -496,12 +511,6 @@ def main():
>                              mirror_select_all)
>      except OVSDBException as oe:
>          print("ERROR: Unable to properly setup the mirror: %s." % str(oe))
> -        try:
> -            ovsdb.destroy_port(mirror_interface, ovsdb.port_bridge(interface))
> -            if tap_created is True:
> -                _del_taps[sys.platform](mirror_interface)
> -        except Exception:
> -            pass
>          sys.exit(1)
>  
>      ovsdb.close_idl()
> @@ -517,12 +526,6 @@ def main():
>      except KeyboardInterrupt:
>          if pipes.poll() is None:
>              pipes.terminate()
> -
> -        ovsdb = OVSDB(db_sock)
> -        ovsdb.destroy_mirror(interface, ovsdb.port_bridge(interface))
> -        ovsdb.destroy_port(mirror_interface, ovsdb.port_bridge(interface))
> -        if tap_created is True:
> -            _del_taps[sys.platform](mirror_interface)
>      except Exception:
>          print("Unable to tear down the ports and mirrors.")
>          print("Please use ovs-vsctl to remove the ports and mirrors created.")
>
> The above 'except' section, should be remove it, if I understand correctlly.
>
>  
>
> I think there was some misunderstanding here.  Sorry about that.
> What I meant is that cleanup_mirror() function should have a
> try-except block and have the 'print's above in the 'except' section.
>
> i.e.
>
> def teardown(...):
>     def cleanup_mirror():
>         try:
>             <destroy a mirror>
>         except Exception:
>             print("Unable to tear down the ports and mirrors.")
>             print("Please use ovs-vsctl to remove the ports and mirrors created.")
>             print(" ex: ovs-vsctl --db=...
>
>     add_hook(cleanup_mirror, None, True)
>
> Okay, I will add try-except block in cleanup_mirror() function again, and prints
> warning.
>
>  
>
> And for the pipes.poll() loop we only need to catch the KeyboardInterrupt.
> No need to catch generic exceptions, IIUC.  The hook will be executed
> anyway, even on the unexpected exception, right?
>
> Right. The third parameter of add_hook indicats the hook function need be run 
> at exiting even on the unexpeted exception.
>
>  
>
> Best regards, Ilya Maximets.
>
> Thanks for your review, @Ilya Maximets. And the following is newer patch 
> according to your suggestions.
>
> ---
>  utilities/ovs-tcpdump.in | 40 ++++++++++++++++++++++------------------
>  1 file changed, 22 insertions(+), 18 deletions(-)
>
> diff --git a/utilities/ovs-tcpdump.in b/utilities/ovs-tcpdump.in
> index 7fd26e405..92cff6d2c 100755
> --- a/utilities/ovs-tcpdump.in
> +++ b/utilities/ovs-tcpdump.in
> @@ -44,6 +44,7 @@ try:
>      from ovs import jsonrpc
>      from ovs.poller import Poller
>      from ovs.stream import Stream
> +    from ovs.fatal_signal import add_hook
>  except Exception:
>      print("ERROR: Please install the correct Open vSwitch python support")
>      print("       libraries (version @VERSION@).")
> @@ -405,6 +406,24 @@ def py_which(executable):
>                 for path in os.environ["PATH"].split(os.pathsep))
>  
>  
> +def teardown(db_sock, interface, mirror_interface, tap_created):
> +    def cleanup_mirror():
> +        try:
> +            ovsdb = OVSDB(db_sock)
> +            ovsdb.destroy_mirror(interface, ovsdb.port_bridge(interface))
> +            ovsdb.destroy_port(mirror_interface, ovsdb.port_bridge(interface))
> +            if tap_created is True:
> +                _del_taps[sys.platform](mirror_interface)
> +        except Exception:
> +            print("Unable to tear down the ports and mirrors.")
> +            print("Please use ovs-vsctl to remove the ports and mirrors"
> +                  " created.")
> +            print(" ex: ovs-vsctl --db=%s del-port %s" % (db_sock,
> +                                                          mirror_interface))
> +
> +    add_hook(cleanup_mirror, None, True)
> +
> +
>  def main():
>      rundir = os.environ.get('OVS_RUNDIR', '@RUNDIR@')
>      db_sock = 'unix:%s' % os.path.join(rundir, "db.sock")
> @@ -489,6 +508,9 @@ def main():
>          print("ERROR: Mirror port (%s) exists for port %s." %
>                (mirror_interface, interface))
>          sys.exit(1)
> +
> +    teardown(db_sock, interface, mirror_interface, tap_created)
> +
>      try:
>          ovsdb.make_port(mirror_interface, ovsdb.port_bridge(interface))
>          ovsdb.bridge_mirror(interface, mirror_interface,
> @@ -496,12 +518,6 @@ def main():
>                              mirror_select_all)
>      except OVSDBException as oe:
>          print("ERROR: Unable to properly setup the mirror: %s." % str(oe))
> -        try:
> -            ovsdb.destroy_port(mirror_interface, ovsdb.port_bridge(interface))
> -            if tap_created is True:
> -                _del_taps[sys.platform](mirror_interface)
> -        except Exception:
> -            pass
>          sys.exit(1)
>  
>      ovsdb.close_idl()
> @@ -518,18 +534,6 @@ def main():
>          if pipes.poll() is None:
>              pipes.terminate()
>  
> -        ovsdb = OVSDB(db_sock)
> -        ovsdb.destroy_mirror(interface, ovsdb.port_bridge(interface))
> -        ovsdb.destroy_port(mirror_interface, ovsdb.port_bridge(interface))
> -        if tap_created is True:
> -            _del_taps[sys.platform](mirror_interface)
> -    except Exception:
> -        print("Unable to tear down the ports and mirrors.")
> -        print("Please use ovs-vsctl to remove the ports and mirrors created.")
> -        print(" ex: ovs-vsctl --db=%s del-port %s" % (db_sock,
> -                                                      mirror_interface))
> -        sys.exit(1)
> -
>      sys.exit(0)
>
> Best regards, Daniel Ding.

Hi Daniel,

Please submit new version as a formal [PATCH v5]
diff mbox series

Patch

diff --git a/utilities/ovs-tcpdump.in b/utilities/ovs-tcpdump.in
index 7fd26e405..b3f764c87 100755
--- a/utilities/ovs-tcpdump.in
+++ b/utilities/ovs-tcpdump.in
@@ -44,6 +44,7 @@  try:
     from ovs import jsonrpc
     from ovs.poller import Poller
     from ovs.stream import Stream
+    from ovs.fatal_signal import add_hook
 except Exception:
     print("ERROR: Please install the correct Open vSwitch python support")
     print("       libraries (version @VERSION@).")
@@ -405,6 +406,17 @@  def py_which(executable):
                for path in os.environ["PATH"].split(os.pathsep))
 
 
+def teardown(db_sock, interface, mirror_interface, tap_created):
+    def cleanup_mirror():
+        ovsdb = OVSDB(db_sock)
+        ovsdb.destroy_mirror(interface, ovsdb.port_bridge(interface))
+        ovsdb.destroy_port(mirror_interface, ovsdb.port_bridge(interface))
+        if tap_created is True:
+            _del_taps[sys.platform](mirror_interface)
+
+    add_hook(cleanup_mirror, None, True)
+
+
 def main():
     rundir = os.environ.get('OVS_RUNDIR', '@RUNDIR@')
     db_sock = 'unix:%s' % os.path.join(rundir, "db.sock")
@@ -489,6 +501,9 @@  def main():
         print("ERROR: Mirror port (%s) exists for port %s." %
               (mirror_interface, interface))
         sys.exit(1)
+
+    teardown(db_sock, interface, mirror_interface, tap_created)
+
     try:
         ovsdb.make_port(mirror_interface, ovsdb.port_bridge(interface))
         ovsdb.bridge_mirror(interface, mirror_interface,
@@ -496,12 +511,6 @@  def main():
                             mirror_select_all)
     except OVSDBException as oe:
         print("ERROR: Unable to properly setup the mirror: %s." % str(oe))
-        try:
-            ovsdb.destroy_port(mirror_interface, ovsdb.port_bridge(interface))
-            if tap_created is True:
-                _del_taps[sys.platform](mirror_interface)
-        except Exception:
-            pass
         sys.exit(1)
 
     ovsdb.close_idl()
@@ -517,12 +526,6 @@  def main():
     except KeyboardInterrupt:
         if pipes.poll() is None:
             pipes.terminate()
-
-        ovsdb = OVSDB(db_sock)
-        ovsdb.destroy_mirror(interface, ovsdb.port_bridge(interface))
-        ovsdb.destroy_port(mirror_interface, ovsdb.port_bridge(interface))
-        if tap_created is True:
-            _del_taps[sys.platform](mirror_interface)
     except Exception:
         print("Unable to tear down the ports and mirrors.")
         print("Please use ovs-vsctl to remove the ports and mirrors created.")