Thanks, and I appreciate all your support and advice.   I have gone through the Link and we got the right set of Stack Cables.   Thanks ... View more

@BrandonS has advised the following steps.   You could try testing them with light. Plugin one end and hold a piece of paper up near the opposite end of the cable and you should see the red light on one strand.  Please be careful to not look directly into the cable with your naked eye.  A dark room can help too.  If you see light with one of your old cables and not with a new one I would say it is bad or was damaged somehow.   Br ... View more

Will carry out the light test tomorrow.   I have briefed my team about it and we look to do this tomorrow.   Thanks ... View more

Meraki Support:   Dear Benedict, Thank you for contacting Cisco Meraki's technical support. The serial numbers you provided for the stack kit don't seem to be Meraki devices. Can you confirm the serial numbers of the Meraki switches you connect your SFP ports too?  Also if you could provide the link to your Meraki dashboard switch network I have a quick look. Kind regards. -- Mahad Gaal Network Support Engineer .?l?.?l?. Cisco Meraki   Response from my suppliers:   Hi Benedict   The cable sure 100% original and should work.   It has to be down to your clients set up and what they are trying to do, it’s the only explanation.   Please give the engineer the Meraki dashboard ID so the engineer can check the client set up. The engineer will be able to see that the cables are genuine, from the Meraki dashboard.     Kind regards,     I have shared the last image with Meraki and all snapshots of the kits and I am still expecting their feedback... ... View more

  Below is the image from my source. That is where my confidence came from... ... View more

We have just MS210s ((MS210-24P-HW & MS210-48LP-HW ) and yes we have followed the physical stacking guide.   is there a link to verify Meraki Products..would like to verify the authenticity of the product.   Thought it was supplied by meraki. ... View more

Thanks. below are the part numbers and description   MA-CBL-40G-50CM Meraki 40GbE QSFP Cable, 0.5 Meter   MA-CBL-40G-1M Meraki 40GbE QSFP Cable, 1 Meter   Regards ... View more

Thanks.   That reminds me, we earlier bought some compatible (Non Meraki) Stack Kits  11 Units 40GbE QSFP Cable 0.5Meter, 2 Units 40GbE QSFP Cable of 1Meter,   and we still had the same issues.   It was then we decided to go for the Original Meraki Kits and still having the same issues.   We fear that another purchase of Kits might end in the same result. ... View more

Below are the serial numbers for the Kits.   SERIAL NUMBERS FOR STACK KIT JPC242904MG JPC242901GY JPC24290495 JPC24290451 JPC242903S4 JPC242904M1 JPC2429048P JPC242904MP JPC24290594 JPC242905X0 JPC2429051Z JPC24290104 JPC242903EK JPC2429047A JPC242903SQ JPC242903KB JPC242904HP JPC242903GH JPC242904BQ JPC242906V2 JPC235003FQ JPC235003DK JPC235003H4 JPC235003H2 JPC235003JP JPC235003EP   I am sure the caps were taken off... ... View more