CW9164I-MR does seem to have a low power mode?

[Paccers]

Hi all,

Thought I would post here in case I am losing my mind but I am seeing something unexpected.

Both the CW9164 Datasheet and CW9164 Installation Guide state that the CW9164I-MR will not power up when running off an 802.3af (15.4W) power source and do not have a low power mode to operate in like the MR44.

Yet, I have multiple sites running CW9164s running on 802.3af power that are powered up, checking in to Meraki Dashboard, show as having an 802.3af power source, have clients connect normally, get DHCP, etc...

I have confirmed that the power value being stated is not incorrect as some of them are patched to PoE switches that also show 15.4W being budgeted on the switchports, some APs are connected to 802.3af power injectors. Checking again just now in fact Dashboard even states 'PoE 802.3af (running in low power mode)' on these 9164 APs

It's not a bad problem to have I guess but I'm not sure what to think... my current real world observations don't match what is stated in Meraki (and Catalyst) documentation? I feel like I'm missing a very obvious glaring bit of information that explains it all

Quick edit: I am in a regulatory domain where I can't enable the 6 GHz radios yet so only running 2.4/5 GHz radios

[alemabrahao]

Are you sure it's running on 802.3af?

[rhbirkelund]

You are correct in the sense that the Meraki documentation seem to state that .3af is not supported. But looking at the Cisco Datasheet for the CW9164I-E AP, it says that the AP will power up, but radios will be down.

Are you able to verify at your sites that clients are connected to the CW9164I-MR AP? And that the APs radios are indeed up?

You can do this perhaps, by taggin the 9164 APs, and configure SSID Availability to broadcast a test SSID only on APs with the tag on the 9164s.

[Paccers]

So I put a 9164 in to our lab today, patched in to a PoE switch where I manually set static power inline max 15400 on the interface, created a basic test SSID only broadcasting from this AP: AP is up and online in Meraki Dashboard with the 'running in low power mode' note in the Access Point details.

My test device saw the test SSID, I can connect + auth fine, local DHCP as usual and external web access as is expected.

Power inline details:

Interface Admin Oper Power Device Class Max
(Watts)
--------- ------ ---------- ------- ------------------- ----- ----
Gi0/1 static on 15.4 Meraki CW9164I Clou 4 15.4

Power levels reported in CDP/LLDP neighbour detail:

CDP:

Power drawn: 15.400 Watts
Power request id: 31193, Power management id: 1
Power request levels are:40000 0 0 0 0 

LLDP:

Power Requested: 25500 mW

Power Allocated: 13000 mW

Meraki Dashboard:

[rhbirkelund]

Interesting.

I think you should open a case with Support then, and inform them of your findings, in regards to perhaps updating the Datasheet and Hardware Installation Guide.

[Paccers]

I'm wondering if it's more of a clarity issue such as 'no radios enabled with 802.3af if you are trying to enable all three client radios' 

Anyone in a 6 GHz approved reg. domain able to replicate running the CW9164 @ 802.3af with all three radios configured for use?

I'll report back with what support make of it all

[Paccers]

Quick update to say that after speaking with support the response was essentially 'this is not a supported operating mode for this model' and that was about it. I asked for documentation to at least be updated to clarify things further and left it at that.

We still want to ensure our 9164s are running at .3at power but at least it's takes some of the user impact away if they run at low power for a short time until the source is fixed up.

[alemabrahao]

It's able to power up, but the antennas will not work:

[Seppi]

Cisco Access Points require the power source as documented in the datasheets.
This is what we built them for, what we test and what we support.

By accident I powered the first CW9164I I got with 802.3af only and I got all kind of effects.
Sometimes it powered and appeared to work, but I had all kind of issues with Wireless traffic.
Sometimes it simply rebooted again and again.
Sometimes it didn't boot at all.
And sometimes it even appeared to work quite fine for some time.

The not booting at all is the worst case that was called out in the installation guide.


At the end it's an untested and unsupported setup.
You really need to provide 802.3at to the CW9164I to get reliable results.

[rhbirkelund]

It makes sense what you are saying, that insufficient power might result in some inconsistent operation.

But in this case there are two sets of documentation which seem to be claiming different things for the same piece of hardware.

One set claims it can boot on .3af. Another says it needs .3at.

[Paccers]

I understand the support scope, but the fact is the docos state it won't even power on when using .3af power and that is not the case with the real-world behaviour, irrespective of any stability-type issues.

The installation guide states outright "The AP will not power up when powered by a single 802.3af power source". The datasheet table suggests the same thing along with the '802.3af not supported' disclaimer.

Do you not agree that after reading the docos it could be confusing for some users who do accidentally power it at .3af, as you stated you did, and find that it does power on and operate as normal?

[alemabrahao]

I think you're the one making the mess.

[Paccers]

I think I'll disagree with that one to be honest @alemabrahao! I'm simply suggesting there could be some better clarity in the official docos that's all.

Have a good one!

[UKDanJones]

It should power up enough for it to do any upgrades needed and join the Org. To use it you’ll want to use 802.1at at least. 

[Paccers]

Support-wise Meraki will only support it when running 802.3at or .3bt, but they do still have radios enabled and servicing clients when running at .3af.

Not that I want to do that of course, it was just surprising at the time of posting to find that it was actually still doing things which were at the odds with the doco wording

[UKDanJones]

Is it consistent? If so it could be a good way to save energy in the evenings or during low occupancy…

[Paccers]

The sites are remote from me but I haven't had support tickets reporting issues, not to say the users just aren't reporting them however!

Have not tested whether it's dropping the radio count and/or RJ-45 speeds when running at .3af though

[UKDanJones]

I suspect both. I’ll have a play today if I have time and report back. 

[redsector]

I bought for a new project 26 CW9164I accesspoints. They are all connected to MS225-48LP switches.

All of the access points are running around 11.3 W with PoE 802.3at. When they are booting or have heavy load then they need more than 15 Watt.