My Oracle Support Banner

Oracle VM: Packet Drops On Interface when IPv6 Not Configured Correctly (Doc ID 2389826.1)

Last updated on JUNE 17, 2020

Applies to:

Oracle Cloud Infrastructure - Version N/A and later
Oracle VM - Version 3.4.4 and later
Information in this document applies to any platform.


On : 3.4.4 version, DomU, Guest VM, Virtual Machine

An Oracle Linux 7.4 have a high number of dropped packets on one interface.

Dropped packets can be verified by:

$ ip -s link
eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP mode DEFAULT qlen 1000
link/ether 00:21:f6:3a:26:bc brd ff:ff:ff:ff:ff:ff
RX:  bytes packets       errors     dropped  overrun mcast
4254067796 6902208   0          213789 0 0
TX: bytes packets errors dropped carrier collsns
1640373770 1216971 0 0 0 0


On the VM run:
$ watch -n 1 ip -s link

On the OVM server check the bridge interface associated with the MAC address of the VM:
# brctl showmacs

Using the returned value (here described as xxx)
# tcpdump -i xxx port \! 22 | grep IP6

Note: Running tcpdump in the VM stop the packet drop increase. This shouldn't happen but has been verified.

Running the two command at the same time it was possible to see that every time a packet was received in the OVM the number of dropped packets increase in the VM.




To view full details, sign in with your My Oracle Support account.

Don't have a My Oracle Support account? Click to get started!

In this Document

My Oracle Support provides customers with access to over a million knowledge articles and a vibrant support community of peers and Oracle experts.