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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal>Hi,<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>We ran into an issue recently that I haven't been able to figure out (this environment is on Stein which uses DVR). It involves an environment with many provider networks that connect to a legacy environment as well as many tenant networks.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>We create a server on a tenant network and add ports to this afterwards with each port attached to its respective provider network. The provider networks have "None" for the "gateway" property, so we don't have multiple default routes added to the routing table.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>We have a single subnet which has DHCP enabled and a proper allocation pool on its subnet.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Note that this is a CentOS 8 server we are testing with, which has "no" ifcfg files for the additional ports, and so we rely on CentOS using DHCP by default.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>After adding the first port, the DHCP client does its job and requests an IP, which succeeds - so the DHCP server in the respective network namespace is responding fine.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>However, after adding the second port, it appears the DHCP client is sending requests out the network (we can see this traffic when tcpdump'ing the respective tap interface on the host), but the DHCP server is not replying. After looking at OpenVSwitch flows, it appears that DHCP broadcast traffic is being dropped for the second network.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>This does NOT happen with tenant networks. I can add multiple ports, each connected to its respective tenant network, and an IP is assigned to each interface that appears in CentOS immediately after the port has been added.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Is there something special that is blocking the creation of the DHCP flow for subsequent provider network ports?<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>NOTE that non-DHCP traffic flows fine if we create an ifcfg file with a static IP set to the address that DHCP should have set the interface to - it just appears that DHCP traffic is not flowing to the DHCP namespace for second and subsequent ports/networks.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Thanks!<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Eric<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p></div></body></html>