<div>
IIRC the ComboC port is the copper port and the ComboF port is the SFP port. <br />
<br />
If you've got a SFP inserted into combo port 1 the copper combo port 1 won't work.<br />
<br />
If you've linked 2 switches using fiber make sure the polarity is correct on the patch cable. &nbsp;Try flipping the connectors at one end (you may need to separate the cables from the retainer clip).
</div>


<div>
Craig Beck is correct. &nbsp;On the combo ports only one of the ports can be active at a time.<br />
<br />
I'm not sure about the SG-300 but on some of the other Cisco switches that had combo ports, the copper ports were active by default and you had to issue a command to activate the fibre ports.
</div>


<div>
Let me describe what I have:<br />
<br />
SG300-52 uplinked using ComboF (multi-mode fiber) to SG300-28<br />
Port G51 &lt;--&gt; Port G27<br />
<br />
This is already there and working.<br />
<br />
I added identical GBIC SFP modules to create a second uplink for:<br />
Port G52 &lt;--&gt; Port G28<br />
<br />
There are 2 GBIC slots in each switch so I assumed that meant I could use both. &nbsp;I didn't notice any differences until I was trying to create the second uplink and noted ComboC vs ComboF.<br />
<br />
The second uplink doesn't work and ports G52, and G28 respectively, show as 'down'.<br />
<br />
Also, to the left of each SFP is an RJ45 port. &nbsp;My understanding is you could the fiber or the copper but not both. &nbsp;Basically, both are G52 or G28. &nbsp;For the uplink that does work the Cisco interface display shows link lights to these corresponding RJ45 ports even though they're empty.<br />
<br />
<a href="https://filedb.experts-exchange.com/incoming/2016/04_w15/1089865/sg300-52.JPG" target="_blank" title="SG300-28 - left ports GBIC top and bottom (G51 - G52) (23 KB)"><img alt="SG300-28 - left ports GBIC top and bottom (G51 - G52)" class="file-block lazyload" style="max-width: 644px;" data-src="https://filedb.experts-exchange.com/incoming/2016/04_w15/1089865/sg300-52.JPG" /></a><br />
Still not clear on what the differences between these ports are or what the ComboC is for.
</div>


SG300-28 - left ports GBIC top and bottom (G51 - G52)

sg300-52.JPG

<div>
ComboC is for a &nbsp;copper (CAT5/CAT6) <br />
<br />
&quot;G51&quot; is for the last 2 top ports on the right. &nbsp;One is for RJ45 copper connection the other is for SFP.<br />
<br />
&quot;G52&quot; is for the last 2 bottom ports on the right. One is for RJ45 copper connection the other is for SFP.<br />
<br />
You should be able to use both G51 and G52.<br />
<br />
So as long as you have nothing the the copper port, you can use the SFP. &nbsp;Look at the configuration for G51 and G52. &nbsp;Like I said before, on some of the devices with combo ports you have to enable or disable on of ports.
</div>


<div>
I have been doing some reading and I have confirmed the same thing. &nbsp;Right now G52 appears to be stuck on ComboC (copper) and isn't recognizing the SPF in the slot. &nbsp;<br />
<br />
When I was onsite I did pull the module and re-insert it. &nbsp;I noted a red laser active on the module in the port but the link indicators still show the port as being down (as per the picture). &nbsp;There isn't a CAT5 cable plugged in to 52 (or 51 for that matter) so as I thought it *should* just come up.<br />
<br />
Apparently others are also complaining about the same thing. &nbsp;The port should auto-detect.<br />
<br />
If I do have to enable the SPF on that port - I am not seeing it in the manual anywhere. &nbsp;Hints?
</div>


<div>
I checking and and for the SG300 it appears that there is no command like on some Cisco switch. &nbsp; It looks like by default it uses the copper port and if it detects an SFP installed it disabled the copper port and uses the SFP port.<br />
<br />
If you have not, which I am assuming you have, I would suggest doing a shut/no shut on the G52 interface.<br />
<br />
What do you get if you do &quot;show interfaces configuration G52&quot;?
</div>


<div>
Good one Craig Beck, we have to do that way too often, especially when going through patch panels.
</div>


<div>
Yep it's a pain! You're right about the SFP auto-detect too. Once a SFP is installed it disables the copper port.
</div>


<div>
Sorry I'm not a fiber guy - only when I have to. &nbsp;Flip the end over? &nbsp;As in MDI/MDIX? &nbsp;The port is set to auto...<br />
<br />
I did confirm that the colours match as well. &nbsp;One is white, one is gray and they are consistent on both sides of the connection. &nbsp;The patch cables (ugly orange things) have 'red' and 'black' ends and they line up with the white and gray.<br />
<br />
I have discovered that these switches have factory/original firmware. &nbsp;(1.0.0.27)<br />
I'm also discovering the hardware that you can't just leapfrog the firmware to the current version so am having to apply multiple firmware upgrades to get it there.<br />
<br />
The GE28 port now show N/A for all fields in the Administration -&gt; Diagnostics -&gt; Optical Module Status which is an improvement - it didn't show up at all before.<br />
<br />
Will keep you updated.
</div>


<div>
Oh yeah, and to be clear I can really only work on one of the switches at the moment. &nbsp;This is a production environment. &nbsp;The SG300-28 has one PC on it and the user is not at his desk much of the day so this is the switch I'm concentrating on. &nbsp;Presumably if I can get this one working then the same process will apply to the SG300-52.
</div>


<div>
Fiber cables don't do auto MDI/MDIX. You'll notice only one side of the SFP has a laser light. That's the TX side. The other is the RX side. You need to put TX on one switch to RX on the other switch, and vice-versa. <br />
<br />
So, at one end of the fiber cable just swap the ends round. That'll reverse the polarity and should bring the link up.
</div>


<div>
Craig you are a genius. &nbsp;Or I am stupid. &nbsp;Or both.<br />
<br />
Flipping the connection solved the issue. &nbsp;The link came up instantly when I swapped Tx and Rx.<br />
<br />
Typically I work offsite so this wasn't an obvious/easy thing to do but when I ran out of other options - it worked.<br />
<br />
Thank you very much both of you. &nbsp;Lesson learned.
</div>


<div>
You're not stupid! It happens to all of us. <br />
<br />
I did say it right in my first post though :)
</div>


<div>
&quot;Fiber cables don't do auto MDI/MDIX. You'll notice only one side of the SFP has a laser light. That's the TX side. The other is the RX side. You need to put TX on one switch to RX on the other switch, and vice-versa. &quot;<br />
<br />
Not sure why but i only have one model no tx/rx sides shown.. <br />
<br />
<a href="http://www.fs.com/products/15465.html" rel="ugc">http://www.fs.com/products/15465.html</a><br />
<br />
i put one in switch A port 52.. one in Switch B port 52..<br />
<br />
On the SG300-52<br />
<br />
<br />
%NSFP-I-SFPGibicDetected: gi52 SFP port is present &nbsp; &nbsp; &nbsp;<br />
<br />
<br />
It detects it… BUT <br />
Optical Module Status<br />
<br />
Optical Module Status Table<br />
Port &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Description &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Serial Number &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;PID &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;VID &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Temperature &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Voltage &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Current &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Output Power &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Input Power &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Transmitter Fault &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Loss of Signal &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Data Ready<br />
GE51 &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;N/A &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;N/A &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;N/A &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;N/A &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<br />
GE52 &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;N/A &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;N/A &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;N/A &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;N/A &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;N/A &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;N/A &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;N/A &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;N/A &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;N/A &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;N/A &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;N/A &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<br />
<br />
<br />
Doesn’t detect in diagnostics NOR<br />
<br />
&nbsp;<a href="http://prntscr.com/d26tes" rel="ugc">http://prntscr.com/d26tes</a><br />
<br />
<br />
Shows has ComboC ?
</div>


<div>
Ports G51 and G52 have two connector types - copper and fiber<br />
<br />
If you have anything plugged into 51 or 52 as copper the switch will not recognize the SFP module in the fiber ports<br />
<br />
What you're describing indicates either the modules are not recognized or G52 copper port is already in use.
</div>


<div>
Ah so its A OR B then no up C AND D. ?<br />
<br />
even if one is up ? <br />
<br />
&nbsp; 51 COPPER , NULL<br />
&nbsp; 52 NULL, FIBER<br />
<br />
if anyone of 51 or 52 has a copper then &nbsp;51 and 52 fiber wont work ?
</div>


<div>
I'm not sure if I understand your description. &nbsp;<br />
<br />
&nbsp;<a href="https://filedb.experts-exchange.com/incoming/2016/11_w45/1125796/2016-11-02-15_22_40-sg300-52.JPG--JP.png" target="_blank" title="2016-11-02-15_22_40-sg300-52.JPG--JP.png (81 KB)"><img alt="2016-11-02-15_22_40-sg300-52.JPG--JP.png" class="file-block lazyload" style="max-width: 566px;" data-src="https://filedb.experts-exchange.com/incoming/2016/11_w45/1125796/2016-11-02-15_22_40-sg300-52.JPG--JP.png" /></a><br />
In the image shown G51F shows a link light. &nbsp;This means G51C cannot be used for Copper because the port is already detecting a Fiber SFP connection. &nbsp;If I plugged in a CAT5e cable to the G51 port I'd lose the Fiber connection.<br />
<br />
You can use G51 as Copper OR as Fiber but not both.<br />
<br />
The same is true for G52.<br />
<br />
That's why it's called a combo port - because it can do either copper or fiber.
</div>


2016-11-02-15_22_40-sg300-52.JPG--JP.png

<div>
no... they are binded...<br />
<br />
51+52... meaning if ANY of 51 or 52 has copper then neither 51 nor 52 can be fiber...<br />
<br />
i had 51 copper.. &nbsp;52 fiber connector.. no go..<br />
moved the 51 copper into 49 .. bang... 52 lit.. 51 lit as well when i put a module int here also..<br />
<br />
so it seems it's an array of somesort where is you are using copper in 51 OR 52 then its copper for both..
</div>


<div>
also note that this has nothign to do with fiber i guess, but speed increased 100 folds from copper BUT<br />
<br />
i had previousely.. <br />
<br />
Switch A to B AND C<br />
Switch B to C<br />
Switch C to B<br />
all daisychained with lags and vlans on seperate ports.. like <br />
<br />
A21 VLAN 1 to B21 VLAN 1 as in 1UP<br />
A22 VLAN 200 to B22 VLAN 200 as in 200UP<br />
etc...<br />
<br />
now i removed all of those and just have <br />
Switch A 51 to Switch B51 Fiber as in 1UP 200T<br />
Switch A 52 to Switch C26 Fiber as in 1UP 200T<br />
<br />
Seems faster but still have Flapping for some reason LLDP neighbour<br />
<br />
there are switches ESX with 6 nicks with 2 cables in each switch so that could be it.<br />
<br />
i guess i should LAG all 6 and put on Switch C all of them instead of splitting right ?
</div>


<div>
News to me that you couldn't use either port (both fiber or copper but not a combination of either) but I can't say I ever tested it. &nbsp;Good to know - I'll tuck that away.<br />
<br />
As for infrastructure - it all depends on what you want to accomplish. &nbsp;Maximum speed vs. maximum failover. &nbsp;ESX does it's own version of NIC teaming so that could conceivably cause problems being split between multiple switches. &nbsp;For failover and shortening paths to different ends of the network it does make sense to split the connections between switches.<br />
<br />
As for the flapping - I had the exact same issue with the bonjour discovery enabled. &nbsp;I turned it off and the problem went away. &nbsp;Not sure if that will help you...
</div>


<div>
yeah but bonjour is needed on clients for the ITunes apple software right , i think that the app that installs this.<br />
<br />
right now esxi is not teemed and 6 legs of it are split in groups of 2 on each switch <br />
<br />
one leg on vlan 1 and one on vlan 200<br />
<br />
ESX A NIC A ---&gt; SWITCH A PORT 1 (Vlan 1) 1UP<br />
ESX A NIC B ---&gt; SWITCH A PORT 2 (Vlan 200) 200UP<br />
<br />
ESX A NIC C ---&gt; SWITCH B PORT 1 (Vlan 1) 1UP<br />
ESX A NIC D ---&gt; SWITCH B PORT 2 (Vlan 200) 200UP<br />
<br />
ESX A NIC E ---&gt; SWITCH C PORT 1 (Vlan 1) 1UP<br />
ESX A NIC F ---&gt; SWITCH C PORT 2 (Vlan 200) 200UP<br />
<br />
something like that<br />
<br />
i think i need to force vlan on the esxi leg and put port in access mode but not sure
</div>


<div>
<div class="content wysiwyg-content">
Have two of these switches already linked using a GBIC fiber module.<br />
I am trying to add a second GBIC filber module link using a different VLAN.<br />
<br />
The second link (added today) shows the G ports as 'down' despite the modules having been inserted and connected correctly.<br />
<br />
So I am now wondering what the difference is between ComboF and ComboC and why the ports appear dead.<br />
<br />
ComboF is working.<br />
ComboC shows as down.<br />
<br />
I read that ComboF is single or multimode fiber linking to Copper Port and ComboC is single or multimode fiber linked to Fiber Port - but I confess I don't really understand the difference or why the ports refuse to come up.
</div>
</div>


Have two of these switches already linked using a GBIC fiber module.
I am trying to add a second GBIC filber module link using a different VLAN.

The second link (added today) shows the G ports as 'down' despite the modules having been inserted and connected correctly.

So I am now wondering what the difference is between ComboF and ComboC and why the ports appear dead.

ComboF is working.
ComboC shows as down.

I read that ComboF is single or multimode fiber linking to Copper Port and ComboC is single or multimode fiber linked to Fiber Port - but I confess I don't really understand the difference or why the ports refuse to come up.

Cisco SG-300 series switches

Cisco PIX is a dedicated hardware firewall appliance; the Cisco Adaptive Security Appliance (ASA) is a firewall and anti-malware security appliance that provides unified threat management and protection the PIX does not. Other Cisco devices and systems include routers, switches, storage networking, wireless and the software and hardware for PIX Firewall Manager (PFM), PIX Device Manager (PDM) and Adaptive Security Device Manager (ASDM).

Cisco

A switch is a device that filters and forwards packets of data between LAN segments. Switches operate at the data link layer or the network layer of the Open Systems Interconnection (OSI) Reference Model and therefore support any packet protocol. LANs that use switches to join segments are called switched LANs or, in the case of Ethernet networks, switched Ethernet LANs. A hub is a connection point for devices in a network. Hubs are commonly used to connect segments of a LAN. A hub contains multiple ports; when a packet arrives at one port, it is copied to the other ports so that all segments of the LAN can see all packets.