ASR 1000 ERSPAN

[Pedro Morais]

Hello All,

When trying to configure ERSPAN on a ASR1006, I'm not getting any traffic on the destination port. ERSPAN flavour is LOCAL SPAN, as described in:

http://www.cisco.com/en/US/docs/ios-xml/ios/lanswitch/configuration/xe-3s/lnsw-conf-erspan.html#GUID-4FF72FB4-CDC4-40CC-AA25-E32C8CE58E95

Configuration used, is the following:

monitor session 1 type erspan-source

no shut

source interface GigabitEthernet0/0/2

destination

erspan-id 10

ip address 10.10.10.1

origin ip address 10.10.0.1

monitor session 2 type erspan-destination

no shut

destination interface GigabitEthernet0/0/3

source

  erspan-id 10

  ip address 10.10.0.1

Output from “show monitor detail”:

ASR1K_1#sh monitor detail

Session 1

---------

Type                   : ERSPAN Source Session

Status                 : Admin Enabled

Description           : -

Source Ports           :

   RX Only           : None

   TX Only           : None

   Both               : Gi0/0/2

Source VLANs           :

   RX Only           : None

   TX Only           : None

   Both               : None

Destination Ports     : None

Filter VLANs           : None

Source IP Address     : None

Source IP VRF          : None

Source ERSPAN ID       : None

Destination IP Address : 10.10.10.1

Destination IP VRF     : None

Destination ERSPAN ID : 10

Origin IP Address     : 10.10.0.1

IP QOS PREC           : 0

IP TTL                 : 255

Session 2

---------

Type                  : ERSPAN Destination Session

Status                 : Admin Enabled

Description           : -

Source Ports           :

   RX Only           : None

   TX Only           : None

   Both               : None

Source VLANs           :

   RX Only           : None

   TX Only           : None

   Both               : None

Destination Ports     : Gi0/0/3

Filter VLANs           : None

Source IP Address     : 10.10.0.1

Source IP VRF         : None

Source ERSPAN ID       : 10

Destination IP Address : None

Destination IP VRF     : None

Destination ERSPAN ID : None

Origin IP Address     : None

IP QOS PREC           : 0

IP TTL                 : 255

Apparently everything is configured in the proper way, however I’m not getting any traffic in the destination port. Also I’ve noticed the following in the details from ‘Session 1’:

Destination IP Address : 10.10.10.1

That doesn’t make much sense to me.

Could anyone help me understand how to configure Local SPAN using ERSPAN?

---

Thanks,

Pedro

[Edison Ortiz]

The source session will have information where to send it (that's the destination IP)

While the destination session will have information from the source.

It looks normal - did you configure 10.10.10.1 as the loopback on this router?

That's a requirement.

[Pedro Morais]

Hi Edison,

I changed the monitor config to match the IP address of loopback0 that I have in this router:

ASR1K_1#sh ip int brief | i Loop

Loopback0              172.25.200.10   YES NVRAM  up                    up     

Loopback100            192.168.200.21  YES manual up                    up     

ASR1K_1#

ASR1K_1#sh run | b monitor

monitor session 1 type erspan-source

source interface Gi0/0/2

destination

  erspan-id 10

  ip address 172.25.200.10

  origin ip address 10.10.0.1

!

!

monitor session 2 type erspan-destination

destination interface Gi0/0/3

source

  erspan-id 10

  ip address 10.10.0.1

!

!

end

However still not working. When I check the destination interface (Gi0/0/3) stats:

ASR1K_1#sh interfaces stats       

GigabitEthernet0/0/0

          Switching path    Pkts In   Chars In   Pkts Out  Chars Out

               Processor      78613  721352514     203867  738528166

             Route cache          0          0          0          0

       Distributed cache     395669  747596509     389077  753024214

                   Total     474282 1468949023     592944 1491552380

Interface GigabitEthernet0/0/1 is disabled

GigabitEthernet0/0/2

          Switching path    Pkts In   Chars In   Pkts Out  Chars Out

               Processor      26765    1712960      26745    1711680

             Route cache          0          0          0          0

       Distributed cache      26768    1713152      27258    2193668

                   Total      53533    3426112      54003    3905348

GigabitEthernet0/0/3

          Switching path    Pkts In   Chars In   Pkts Out  Chars Out

               Processor          9        540          0          0

             Route cache          0          0          0          0

       Distributed cache       4980    1040936          0          0

                   Total       4989    1041476          0          0

Any idea?

---

Thanks,

Pedro

[faradajay]

Hi, Change IP 10.10.10.1 to 172.25.200.10 in your ERSPAN  source and destination session. Both session must have same IP in ERSPAN when you are using it as local span.

[paul driver]

Hello
The destination address, is that of a routed or svi interface, quite sure the destination needs to be the ip address of the svi to which the destination physical port resides in.