vwire unequal packet/bytes count

cancel
Showing results for 
Show  only  | Search instead for 
Did you mean: 
Announcements
Please sign in to see details of an important advisory in our Customer Advisories area.

vwire unequal packet/bytes count

Hello!

So, we have a very simple lab topology with virtual-wire and a single "allow all" policy.

I think it is important to note that on the egress interface is a single host that should not be generating any traffic (or minimum traffic). The ingress port is connected to a span port on a switch. I am aware that it is a strange setup Smiley Happy, but that's how it is

We have noticed strange counter values for the interfaces in the virtual-wire:

(partial "show interface" output)

ingress interface, ethernet1/13

Logical interface counters read from CPU:

--------------------------------------------------------------------------------

bytes received                           423819043242

bytes transmitted                        64288

packets received                         434867911

packets transmitted                      434

receive errors                           0

packets dropped                          14021012

packets dropped by flow state check      349811

egress interface, ethernet1/4

Logical interface counters read from CPU:

--------------------------------------------------------------------------------

bytes received                           63096

bytes transmitted                        312976866931

packets received                         427

packets transmitted                      342360077

receive errors                           0

packets dropped                          0

There is a huuuuuuge difference between the number of tx and rx packets on each interface, and I think they should be more or less equal, considering the configuration/topology.

It is a 3020 box running 5.0.8

2 REPLIES 2

L6 Presenter

Hi...You mentioned that the ingress is connected to a span port.  Do you know what traffic you are mirroring to the span port?  If the mirrored traffic contains vlan tagged packets, those may not be transmitted across the vwire unless you enable tagging on the vwire setting.  Also, non-tcp-syn traffic will not be transmitted by default since vwire is performing stateful inspection. 

i am not sure about the configuration on the switch side, as i was not involved int the POC from the beginning, but i can presume that it is a trunk port... all vlans should go through, the vwire has all 0-4094 tags enabled to pass through. also, the reject non-syn packets option is turned off, so i am certain that (almost) everything should be transmitted.

here is the full output from the interfaces

admin@PA-3020> show interface ethernet1/4 (egress interface)

Name: ethernet1/4, ID: 19

Link status:

  Runtime link speed/duplex/state: 1000/full/up

  Configured link speed/duplex/state: auto/auto/auto

MAC address:

  Port MAC address 00:1b:17:c0:be:13

Operation mode: virtual-wire

Untagged sub-interface support: no

--------------------------------------------------------------------------------

Name: ethernet1/4, ID: 19

Operation mode: virtual-wire

Interface management profile: N/A

Service configured:

Zone: span, virtual system: vsys1

Adjust TCP MSS: no

--------------------------------------------------------------------------------

--------------------------------------------------------------------------------

Physical port counters read from MAC:

--------------------------------------------------------------------------------

rx-broadcast                  30

rx-bytes                      114543

rx-multicast                  717

rx-unicast                    0

tx-broadcast                  212639

tx-bytes                      355186826330

tx-multicast                  1423373

tx-unicast                    412349668

--------------------------------------------------------------------------------

Hardware interface counters read from CPU:

--------------------------------------------------------------------------------

bytes received                           63096

bytes transmitted                        312976866785

packets received                         427

packets transmitted                      342360076

receive errors                           0

packets dropped                          0

--------------------------------------------------------------------------------

Logical interface counters read from CPU:

--------------------------------------------------------------------------------

bytes received                           63096

bytes transmitted                        312976866931

packets received                         427

packets transmitted                      342360077

receive errors                           0

packets dropped                          0

packets dropped by flow state check      0

forwarding errors                        0

no route                                 0

arp not found                            0

neighbor not found                       0

neighbor info pending                    0

mac not found                            0

packets routed to different zone         0

land attacks                             0

ping-of-death attacks                    0

teardrop attacks                         0

ip spoof attacks                         0

mac spoof attacks                        0

ICMP fragment                            0

layer2 encapsulated packets              0

layer2 decapsulated packets              0

--------------------------------------------------------------------------------

admin@PA-3020> show interface ethernet1/13  (ingress interface)

--------------------------------------------------------------------------------

Name: ethernet1/13, ID: 28

Link status:

  Runtime link speed/duplex/state: 1000/full/up

  Configured link speed/duplex/state: auto/auto/auto

MAC address:

  Port MAC address 00:1b:17:c0:be:1c

Operation mode: virtual-wire

Untagged sub-interface support: no

--------------------------------------------------------------------------------

Name: ethernet1/13, ID: 28

Operation mode: virtual-wire

Interface management profile: N/A

Service configured:

Zone: Srce, virtual system: vsys1

Adjust TCP MSS: no

--------------------------------------------------------------------------------

--------------------------------------------------------------------------------

Physical port counters read from MAC:

--------------------------------------------------------------------------------

rx-broadcast                  214342

rx-bytes                      658550534846

rx-multicast                  1446046

rx-unicast                    697011884

tx-broadcast                  31

tx-bytes                      115594

tx-multicast                  722

tx-unicast                    0

--------------------------------------------------------------------------------

Hardware interface counters read from CPU:

--------------------------------------------------------------------------------

bytes received                           423820609551

bytes transmitted                        64288

packets received                         434884177

packets transmitted                      434

receive errors                           16266

packets dropped                          0

--------------------------------------------------------------------------------

Logical interface counters read from CPU:

--------------------------------------------------------------------------------

bytes received                           423819043242

bytes transmitted                        64288

packets received                         434867911

packets transmitted                      434

receive errors                           0

packets dropped                          14021012

packets dropped by flow state check      349811

forwarding errors                        0

no route                                 0

arp not found                            0

neighbor not found                       0

neighbor info pending                    0

mac not found                            0

packets routed to different zone         0

land attacks                             0

ping-of-death attacks                    0

teardrop attacks                         0

ip spoof attacks                         0

mac spoof attacks                        0

ICMP fragment                            0

layer2 encapsulated packets              0

layer2 decapsulated packets              0

--------------------------------------------------------------------------------

  • 2082 Views
  • 2 replies
  • 0 Likes
Like what you see?

Show your appreciation!

Click Like if a post is helpful to you or if you just want to show your support.

Click Accept as Solution to acknowledge that the answer to your question has been provided.

The button appears next to the replies on topics you’ve started. The member who gave the solution and all future visitors to this topic will appreciate it!

These simple actions take just seconds of your time, but go a long way in showing appreciation for community members and the LIVEcommunity as a whole!

The LIVEcommunity thanks you for your participation!