This issue might occur if one of the following conditions exists:
Conditions that cause issue "VMs in the same subnet on the same host cannot reach each other."
Incorrect link aggregation configuration.
Incorrect VLAN configuration.
Packet loss on the switch.
To resolve the issue:
Verify VM settings and configurations on the vnet interfaces that connect the VMs to the OVS. For more information, see "VMs in the same subnet on the same host cannot reach each other."
Verify that packets can be forwarded out of the OVS. Use the # tcpdump –lni <eth_name> -Q out command to capture packets on each member port of the OVS aggregate interface to verify packets can be forwarded out of the OVS. You can use the # ovs-appctl bond/show <ovs_bond> command to view the member ports of an aggregate interface.
If packets cannot be forwarded out of the OVS, examine security group, IP binding, and MAC binding settings on the vnet interface that connects VM 1 to the OVS to identify the configuration that causes the packet drop.
If packets can be forwarded out of a physical interface on the OVS, proceed to the next step.
Log in to the host where VM 2 resides, and capture packets to the OVS on the physical port that connects to VM 2.
If ARP packets from VM 1 cannot be captured or packet loss was detected, proceed to step four.
If ARP packets from VM 1 can be captured, proceed to step five.
Verify link aggregation configuration on the OVS and the switch.
If basic or advanced static aggregation is configured, an aggregation group must also be configured on the peer switch and all physical ports of the OVS aggregation must be added to the group.
If active/standby static aggregation is configured, you cannot configure aggregation groups on the peer switch. If you do so, packet loss will occur.
If dynamic aggregation is configured, an aggregation group must also be configured on the peer switch and LACP must be enabled. If the aggregation group is configured correctly, verify VLAN settings on the switch port. If the issue persists, contact Technical Support.