ifconfig shows dropped rx packets
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After updating to SLES 11 SP2 or any version after, packets are being dropped
Dropped counter incrementing
rx_dropped counter is incrementing
Customers have reported seeing dropped packets when examining statistics on their network card, bonds, or virtual interfaces.
Softnet backlog full -- (Measured from /proc/net/softnet_stat)
Bad / Unintended VLAN tags
Unknown / Unregistered protocols
IPv6 frames when the server is not configured for IPv6
If any frames meet those conditions, they are dropped before the protocol stack and the rx_dropped counter is incremented.
host:~# ifconfig <interface> promisc
And then watching the rx_dropped counter. If it stops incrementing while the NIC is in promiscuous mode; then it is more than likely showing drops because of the reasons listed earlier.
Within SLE products, the idea that dropped packets are now normal and expected started in SLES 11 SP2, as it utilizes a 3.x kernel. Previous SLES versions do not exhibit it, as they use kernels prior to 2.6.37
Additional information can be found by researching commit # caf586e5
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- Document ID:7007165
- Creation Date: 17-May-2012
- Modified Date:03-Mar-2020
- SUSE Linux Enterprise Server
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