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<p class="MsoNormal">Hi,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Currently in OVS we set “-1” for ofport field in interface table of OVS DB when we fail to initialize the interface. This means if we had allocated any ofport number earlier, it is released. When the above failed interface gets initialized
successfully later it gets a “new” ofport number again. Due to change in ofport number, any SDN controller will have to change all the openflows corresponding to this interface (due to change in port number). I am not sure why we release the ofport number
for the interface, unless it is deleted from the interface table itself.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Does it make sense to preserve the ofport number as long as the interface is present in OVS DB and release it once it is deleted? This will help controller not to modify existing flows but only replay (resync) the same, once interface comes
back alive.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Need some guidance here how to handle such cases.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Warm Regards,<o:p></o:p></p>
<p class="MsoNormal">Vishal Ajmera<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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