Intermittent sensor connectivity with Sensor Hub - Specific ports

Hello,

I've run into an issue with sensors (temperature/humidity sensor units, 5 per hub) dropping off intermittently when connected via the sensor hub, but only on ports 5&6. All other sensors are stable and work as expected. The sensors show as down on the web interface, and return nothing via snmp. Firmware is current on all 3 sensor bases (two installed, plus the one setup for testing purposes)

To rule out a cabling issue, I've setup a sensor base, hub and two sensors in another location using short pre-made cables and I was able to replicate the issue on port 5. Port 5 seems to exhibit the worst symptoms, but 6 is intermittent as well.

Equipment was recently purchased, and have March of 2018 serial numbers. We have other sensors purchased over the last few years, but none are using the hubs, and have not exhibited any similar symptoms.

Any assistance on this would be greatly appreciated.

Cheers!
Perry

How fast and how frequent does the Sensor on port 5 / 6 becomes intermittent?

Are you using PoE? If you have a BASE-PWR (power adaptor) could you try it also and see if it will still be intermittent

Hi Dhane,

The sensors drop out fairly randomly every few minutes, sometimes they will come back within 30 seconds or so, other times they will be out for several minutes. I have yet to pick out any pattern in the behaviour. I've attached an image from our monitoring system that shows the behaviour a bit better.

They are powered via PoE from a Cisco 2960x-48FPS-L with plenty of power in reserve. We do not have any of the power adaptors available for test as PoE is a requirement for this installation.

Cheers!
Perry

Hi,

Have you tried swapping sensors from the other ports? Just to rule out which is causing the problem.
The Sensor that you use on the ports 5&6 to other port.
A Sensor that works fine on other port put it on Ports 5&6?

Hi Dhane,

I've swapped sensors around between ports to confirm that it follows the port and not the sensor. I'm seeing the identical behaviour across 3 hubs so far from this order. Number of sensors does not seem to impact it at all as it behaves the same with 2 sensors as it does with 5.

Cheers!
Perry

What sensor do you have connected on port 5 and what polling interval have you set?

Hi Perry,

Instead of using port 5 for 1 ENV-THUM, could you try and use port 7 to test?

Hi Administrator, Dhane,

Then sensor is the temperature/humidity, and I've tested everything from a 1 second and a 5 second polling time. I've found the sensors that are dropping out seem to come back online more consistently with a 1 second polling time.

I'll try moving the sensor over to port 7 on my test setup this afternoon and report back.

Cheers!
Perry

Hi Dhane,

I've moved the sensor from port 5 to port 7 to test, and so far it appears to be stable. I'll keep an eye on it for the next few days.

Cheers!
Perry

bbits said:

Hi Dhane,

I've moved the sensor from port 5 to port 7 to test, and so far it appears to be stable. I'll keep an eye on it for the next few days.

Cheers!
Perry

Hi,
That's good to hear

Hi Dhane,

I've also now tested moving the sensor to port 8 and it appears to be exhibiting similar symptoms to port 5, so only port 7 on that side seems to be stable.

Cheers!
Perry

May i know what is your software's polling time?

Hi Dhane,

I'm currently polling the production sensors every 10 seconds on one platform (collectd), and every 5 minutes on another (observium), but this issue shows up on the sensor UI page as well without being polled by any external software.

Polling on both platforms is using SNMP.

Perry

Hello,

Following up on this as I really need to get this issue resolved.

Cheers!
Perry

have you tried updating to the latest firmware? It seems some sensors was stable on the update so was thinking if it would also do good on hub

Base is running latest firmware (these were manufactured in March of this year). Is there firmware available for the hub itself?

I had looked around but was unable to find anything specific for the hub, but reloaded the latest firmware on the base with the hub attached to see if it made any difference, but no changes in behaviour.

Thanks,
Perry

The latest 7.5 firmware was release just this month, as it stabilised my sensors, i was assuming it would help you too

bbits said:

Base is running latest firmware (these were manufactured in March of this year). Is there firmware available for the hub itself?

I had looked around but was unable to find anything specific for the hub, but reloaded the latest firmware on the base with the hub attached to see if it made any difference, but no changes in behaviour.

Hi,
Firmwares are only available for the Base-Units.

bbits said:

Hi Dhane,

I'm currently polling the production sensors every 10 seconds on one platform (collectd), and every 5 minutes on another (observium), but this issue shows up on the sensor UI page as well without being polled by any external software.

Polling on both platforms is using SNMP.

Perry

When the sensor drops does it remain on the UI or it has an X-mark on the state column of the sensor?
And also have you tried changing the cables from the Gateway to the Hub?

Sensor shows the X mark on the state column, and the sensor count changes on the main status screen. If you refresh the sensor status page when it shows them as down they will disappear from the list until they start responding again.

Multiple cables and sensors have been tried across all 3 sensors, always follows the port.

I've also tried changing out the cables between the hub and the base with no changes. Cables have also all been tested and are OK.

I'll try the 7.5 firmware update on my test array and report back if anything changes.

Thanks,
Perry

I've updated my test sensor array to version 7.5, but no change in the sensor behaviour for port 5.

Hello Perry, have you tried to switch the current PoE set-up to other PoE ports of your Cisco 2960x-48FPS-L?
How many devices are connected to your Cisco 2960x-48FPS-L?

Hi Schmitt,

I'm currently running them on two different switches, both have plenty of power budget free (I'm currently using maybe 35 watt out of 740 on each), and only 15 or so total devices connected per switch.

Issue is with the hub for sure as it follows the specific ports and does not seem to matter if only one sensor is connected, or all 8. The sensors connected to ports 1-4 are rock solid both on the base web UI as well as through SNMP.

Thanks,
Perry

I'm not sure but might be a problem or bug as both of your hubs are affected, well use other ports like port 7 where your sensor was stable