Poor range since replacing MR33 with CW9172I

[jrhop]

We have been running MR33's on our 30+ locations and range and performance had been good for many years. We have now replaced some sites with CW9172I's and had very bad issues with wireless range. Coverage in the same areas is significantly worse than with the MR33. We have tried changing radio settings, transmit power etc, disabling 6GHZ, changing it to run with 2 x 5GHz. However nothing improves the performance. I cant believe the replacement 'upgraded' access point can be so much worse.

Anyone else seen similar issues?

[alemabrahao]

Could you share your RF profile settings with a screenshot, please?

[jrhop]

Sure, this is one site

This is another where we have tried turning off 6Ghz and changing it to run with 2 radios instead of 3, none of the settings increase performance. With the MR33's we pretty much had everything set to auto and had no issues and good performance.

[alemabrahao]

The only observation I would make is to avoid using an 80 MHz bandwidth for the 5 GHz band, considering you only have 6 available channels with that configuration.

If possible, also avoid using the 2.4 GHz band. Otherwise, I don't see any configuration problems.

But just to understand better, are you only having performance issues? Is coverage all okay?

Maybe this document will help you.

https://documentation.meraki.com/MR/Troubleshooting_and_Support/Troubleshooting/Tools_for_Troublesho...

[jrhop]

Thanks @alemabrahao Some sites auto switched to 160MHz with the new APs, but we changed them to 80Mhz, we running 80Mhz with the MR33's with no issues. We could try turning off 2.4GHz, but clients are connected to 5Ghz, so doubt it will increase coverage.

Sorry to clarify, coverage is the issue we are having. CW9172 APs in the same location as the previous MR33's were provide much worse coverage. Changing settings one by one and testing doesn't make any difference. It seems the hardware (or firmware) is just worse.

[alemabrahao]

What firmware version are you running?

[jrhop]

We set all networks to the latest stable release MR 31.1.8, which appeared to be successful however when you look at some APs it says status 'skipped' or 'started', but no change for days/weeks. Looks like there is a post about this, but not recent update on the status, assume still broken. So unless someone can tell me where to find what the APs are actually running, as I can't see it anywhere https://community.meraki.com/t5/Wireless/Issue-Affecting-CW9172I-and-CW9172H-Access-Point-Upgrades-t...

[MarcP]

Having a look into details, seems like the different antennas/antenna design can be a problem.

I would disable 6GHz, try to lower "max Tx Power" on 5GHz

APs mounted under the ceilling (straight)?

Maybe the heatmap shows some more details, regarding to placement.

[jrhop]

Thanks @MarcP We have disabled 6GHz on one of the sites and changed the radio to run in 2 x 5GHz instead of 6GHz, neither configuration makes a different to coverage. We have adjusted power up and down and had set to auto, again neither impact coverage. APs are ceiling mounted, the same place as MR33's were.

[alemabrahao]

One small detail about the CW9172I is that it's optimized for high data transfer rates, not long range, so it uses smaller omnidirectional antennas and is designed for dense environments.

Perhaps the CW9162 would be a better replacement.

Did you consult your Cisco sales representative before planning the replacement?

[jrhop]

Thanks @alemabrahao Do you have a link to official documentation on this? We were told by our Meraki rep that CW9172I would be a direct like for like replacement of the MR33's in the current lineup.

[alemabrahao]

The Cisco Wireless 9172 Series Wi-Fi 7 access points are high-performance wireless solutions designed for environments like healthcare clinics, retail stores, and distributed business locations such as regional branches and logistics hubs. With tri-radio functionality across 2.4-GHz, 5-GHz, and 6-GHz bands, the 9172 Series provides reliable, high-speed connectivity (up to 9000 Mbps) for spaces with low to moderate device density. Flexible deployment options—cloud, on-premises, or hybrid—allow seamless integration into existing networks.

CW9172I Datasheet - Cisco Meraki Documentation

Though not in terms of “long-range” marketing language. The official Cisco documentation and datasheets clearly position the CW9172I for low to moderate density environments and emphasize high-performance connectivity rather than extended coverage.

[jrhop]

Thanks @alemabrahao These APs are in branch offices and I would consider them low density, 5-10 clients max. We were told that they were like for like replacements with MR33's which are also general use/low density APs.

[MarcP]

Antenna Patterns:
https://www.cloudwifiworks.com/mr33.asp

https://www.cisco.com/c/en/us/products/collateral/wireless/catalyst-9100ax-access-points/wireless-91...

[jrhop]

Thanks @MarcP based on that I would interpret the CW9172I to be slightly better or at least the same as the MR33

MR33

CW9172I

[alemabrahao]

It depends; there may be other factors interfering with the coverage, such as interference, for example. Take a look at these links.

https://documentation.meraki.com/MR/Troubleshooting_and_Support/Troubleshooting/Wireless_Issue_Resol...

https://documentation.meraki.com/MR/Troubleshooting_and_Support/Troubleshooting/Tools_for_Troublesho...

I also advise you to conduct a site survey, as these are antennas with different characteristics. And simply changing antennas won't always result in an improvement; ideally, a survey should always be done before and after installation.

[jrhop]

Thanks @alemabrahao there is no issues with interference which is flagged in the portal. APs are in the same positions as MR33's.

[RaphaelL]

What is the actual transmit power used by the APs ?

[jrhop]

@RaphaelL Thanks, first one below shows a site where we tried to increase transmit power. Second one is from a site set to auto, same as MR33's were.

[ww]

I think 18dbm is the max for a 4x4 AP with beamforming on the UNII-1/2 channels. So if this is calculated with the auto setting it looks like you might need more AP's. To be sure you could do a site-survey. Were your mr33 also on 18dbm or higher?

The mr33 was 2x2 and was probably going to max 21 dbm. 

Maybe that somehow just did work  better for your environment.

[pjc]

I found similar reduced range when moving from MR32 to MR36 and MR44.  Not hugely scientific, but I did a number of tests where I had one of each model AP (MR32, MR36 and MR44) located alongside each other with my laptop a distance away in an office.  My signal level was better with the MR32 versus the newer MR36 and MR44 models.  The AP speedtest on the AP management (my.meraki.com) also produced better throughput on the MR32 than the other newer models.  All power/channel settings to AUTO

[jrhop]

Thanks for your input @pjc On some sites before we put in CW9172's we did deploy some MR36's and these were almost the same in terms of coverage with the MR33's. Therefore we assumed (wrongly) that the CW9172's would be the same or similar, but looks like we were wrong and the CW9172 do not perform as well.