Strange Case - Port numbering on the Catalyst switch WS-C3560CX-12PD-S

[Hannibal]

Hi Community, the best of the internet

Let me ask the following query:

We are going to configure a switch for one of our remote offices. It is the first time that we have acquired a Cisco switch as small as the WS-C3560CX-12PD-S model.

The technical specifications are as follows:

1. Uplink Interfaces: 2 x 1G copper plus 2 x 10G SFP+
2. Ports: 12 x 10/100/1000 Gigabit Ethernet
3. PoE Output Ports: 12 PoE+
4. Other ...
5. I have inserted the picture of the front pannel so you can see that.

Right now we are a bit surprised because with the show running command, two additional ports appear (interface GigabitEthernet1/0/15 and interface GigabitEthernet1/0/16) which we cannot match physically.

We have inserted on interface TenGigabitEthernet1/0/1 one SFP or GIBIC of 1-Giga of bandwidth.

Please, someone from the community has had this experience or can send a Cisco link to the explanation??

switch#sh run

...

interface GigabitEthernet1/0/1
interface GigabitEthernet1/0/2
interface GigabitEthernet1/0/3
interface GigabitEthernet1/0/4
interface GigabitEthernet1/0/5
interface GigabitEthernet1/0/6
interface GigabitEthernet1/0/7
interface GigabitEthernet1/0/8
interface GigabitEthernet1/0/9
interface GigabitEthernet1/0/10
interface GigabitEthernet1/0/11
interface GigabitEthernet1/0/12
interface GigabitEthernet1/0/13
interface GigabitEthernet1/0/14
interface GigabitEthernet1/0/15
interface GigabitEthernet1/0/16
interface TenGigabitEthernet1/0/1
interface TenGigabitEthernet1/0/2

Thanks in advance Community, the best of the internet..

Hann.

[paul driver]

Hello
They’ll will relate to SFP insertion type on port 1/2 (gig1/015, gig1/0/16) be it either copper or fibre.

[Hannibal]

Hi Paul

Thank you very much!!
This means that we must configure the port interface GigabitEthernet1/0/15 (logical) instead of port interface TenGigabitEthernet1/0/1 (physical) where the GBIC module (-Giga) is inserted?

Both interfaces number of interfaces appear in the configuration menu.

Thanks in advance

Hann

[paul driver]

Hello

Correct.

[Leo Laohoo]

Those two SFP ports can support SFP (1 Gbps) and SFP+ (10 Gbps).

[Hannibal]

Hi Leo,

Thank you very much for your reply...

Now I understand that if I insert a SFP (1GB), I must configure the interface GigabitEthernet1/0/15 or 1/0/16  instead of the interface TenGigabitEthernet1/0/1 

And if I insert a SFP+ (10GB), then we must configure the interface TenGigabitEthernet1/0/1 or 1/0/2 instead of interface GigabitEthernet1/0/15 or 1/0/16. It isRight ???

Thanks in advance...

and kind regards

Hann

[paul driver · Accepted solution]

Hello

correct 

[Hannibal]

Thanks Paul..

Hann