FW Monitor

R80.x Performance Tuning and Debug Tips – fw monitor

R80.20 – fw monitor

Tip 1

SecureXL has been significantly revised in R80.20. It now works in user space. This has also led to some changes in “fw monitor”.

Since R80.20  “fw monitor” is able to show the traffic accelerated with SecureXL. Thus it is possible to see SecureXL (provide more performance) modules in fw monitor chain. For more informations revert to “SecureXL offloading chain modules” in this article. Now you can see that SecureXL is used, which increases the performance of the firewall.

SecureXL “fwaccel off” does not have to be disabled on R80.20 to run “fw monitor”. This is good for performance, so “fw monitor” does not affect performance any more.

# fwaccel off                                      > no longer necessary in R80.20 and above

# fw monitor -e “accept(…);”

R77.30 and R80.10 – fw monitor

On R77.30 and R80.10 only disabling SecureXL allows to see the complete connection in fw monitor, which may be required for troubleshooting purposes or revert to “How to disable SecureXL for specific IP addresses”.

# fwaccel off                            

# fw monitor -e “accept(…);”

New fw monitor inspection points in R80.20

Tip 2

Furthermore there are new fw monitor inspection points available:

Inspection point Name of fw monitor inspection point Relation to firewall VM Available since version
i Pre-Inbound Before the inbound FireWall VM always
I Post-Inbound After the inbound FireWall VM always
id Pre-Inbound VPN Inbound before decrypt R80.20
ID Post-Inbound VPN Inbound after decrypt R80.20
iq Pre-Inbound QoS Inbound before QoS R80.20
IQ Post-Inbound QoS Inbound after QoS R80.20
o Pre-Outbound Before the outbound FireWall VM always
O Post-Outbound After the outbound FireWall VM always



Pre-Outbound VPN*

Outbound before encrypt 





Post-Outbound VPN*

Outbound after encrypt



oq Pre-Outbound QoS Outbound before QoS R80.20
OQ Post-Outbound QoS Outbound after QoS R80.20

* The fw monitor inspection point is different in R80.10 (“e” or “E”) and R80.20 (“oe” and “OE”)

For more information, see sk30583, fw monitor or How to use FW Monitor.

SecureXL offloading chain modules

Tip 3

Like I said SecureXL has been significantly revised in R80.20. It now works in user space. This has also led to some changes in “fw monitor”

There are new fw monitor chain (SecureXL) objects that do not run in the virtual machine.

# fw ctl chain

The new fw monitor chain modules (SecureXL) do not run in the virtual machine (vm).
SecureXL inbound (sxl_in)                 > Packet received in SecureXL from network
SecureXL inbound CT (sxl_ct)           > Accelerated packets moved from inbound to outbound processing (post routing)
SecureXL outbound (sxl_out)            > Accelerated packet starts outbound processing
SecureXL deliver (sxl_deliver)          > SecureXL transmits accelerated packet

New VM chain modules in R80.20

Tip 4

There are more new chain modules in R80.20

vpn before offload (vpn_in)                  > FW inbound preparing the tunnel for offloading the packet (along with the connection)
fw offload inbound (offload_in)            > FW inbound that perform the offload
fw post VM inbound  (post_vm)            > Packet was not offloaded (slow path) – continue processing in FW inbound

# fw ctl chain 

New fw monitor chain key (00000000)

Tip 5

In Firewall kernel (now also SecureXL), each kernel is associated with a key (red) witch specifies the type of traffic applicable to the chain modul.

 # fw ctl chain 

Key Function
ffffffff IP Option Stip/Restore
00000001 new processed flows
00000002 wire mode
00000003 will applied to all ciphered traffic (VPN)
00000000 SecureXL offloading (new in R80.20+)



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