HP Service Insertion Guide K/KA/WB.15.15

Troubleshooting helpPossible causeIssueID
controller, it could be for one of the
following reasons
• MTU violation during
encapsulation can cause packets
to be dropped.
• Uplink interface drops (link
congestion).
• Network congestion in the
upstream network.
Service Tunnel Statistics
MTU Violation Drop : 10
Relevant MIB objects:
hpicfServiceTunnelStatsTxMTUViolationDrop
(hpicfServiceTunnels MIB)
If there are no MTU violation related
drops, run the following command to
know if there are uplink interface TX
drops.
To do that, first determine the uplink
interface that this tunnel uses by
running the “show interface tunnel
type intercept” command and identify
the ‘Egress port’.
HP-3800-SW$ show interface
<port>
Look for TX drop counters on this
interface.
Run the following CLI command and
check if the ifindex in the tunnel used
is valid.
Stale tunnels
When a tunnel is deleted but an
OpenFlow rule that is diverting
DNS/IP packets not sent out to the
tunnel.
8
HP-3800-SW$ show interface
tunnel type intercept
packets to that tunnel interface is still
not removed, packets to the stale
tunnels are dropped.
Interface Index :
1000000001
Relevant MIB objects:
tunnelInetConfigIfIndex
(rfc4087 MIB)
Also in this case, the tunnel rule hit
count increases as packets match the
tunnel rule.
Decapsulation path
Troubleshooting helpPossible causeIssueID
Run the following CLI command to know if
there are drops due to GRE KEY
incompatibilities.
GRE Key incompatibility
If the GRE KEY in the encapsulated
packet does not match one of the
Tunneled packets received
from the remote endpoint not
decapsulated at the switch.
1
HP-3800-SW$ show interface
tunnel type intercept statistics
configured tunnels’ GRE KEY values,
encapsulated packets can be
dropped.
Service Tunnel Statistics
Packets to Non-Existent Tunnels:
200
If this counter is incrementing, it means there
is GRE KEY incompatibility in traffic
inbounds on one or more tunnels.
Relevant MIB objects
hpicfServiceTunnelStatsRxInvalidKey
(hpicfServiceTunnels MIB)
Run the following CLI command to know if
there are drops due to fragmentation.
IP fragmentation
If the GRE KEY matched that of a
configured tunnel but the packet was
Encapsulated packets
received from the remote
endpoint not decapsulated at
the switch.
2
HP-3800-SW$ show interface
tunnel type intercept statistics
a fragmented frame (‘More
Service Tunnel Statistics
Fragments Bit’ set), the switch cannot
Fragmented Packets Dropped (Rx):
100
re-assemble these frames and
therefore will drop them.
22 Service Insertion