MQTT server is offline

matt216 · Nov 17, 2020, 11:07 AM

Also, very occasionally, get the notification:
“MQTT Error. The MQTT client has suffered an error: Error: getaddrinfo EAI_AGAIN io.adafruit.com”

Would appreciate a steer in the direction of any logs I can dig in to.

Thanks

sdetweil · Nov 17, 2020, 12:55 PM

@matt216 eai_again in a name server problem. See that a lot when people are using advert filters like Pinole, or have unstable internet

matt216 · Nov 18, 2020, 3:42 PM

Thanks @sdetweil . I do indeed have Pihole running on my network. Yesterday I observed the “MQTT offline” mirror notification exactly at the same time as a (successful) A and AAAA request from the mirror for the MQTT server URL.
Today, however, the notification appeared but there is no corresponding DNS request from the mirror.
This is the first module (and only device on my network) that struggles… not convinced it is DNS related.
Appreciate the help.

sdetweil · Nov 18, 2020, 3:47 PM

@matt216 the error is dns failure

matt216 · Nov 20, 2020, 5:33 PM

I can ‘force’ this error by turning off the nearest wifi access point that the mirror uses on my home network. Although the mirror associates with another AP the connection to the MQTT server is broken and will not re-establish.
This error only occurs occasionally, usually, which would make sense as the nearest access point is… ‘flaky’, shall we say (it’s a powerline adaptor type).
I am going to specify a certain (reliable) AP for the mirror to connect to. Otherwise I may try a different ssid for the second AP (keen to avoid this, though).
Thanks for help so far.

sdetweil · Nov 20, 2020, 6:17 PM

@matt216 i M glad that you were able to recreate and have a plan to resolve.

I had a similar problem w my wifi security cams and an mm system.

Finally replaced the networking w a Google wifi system, where I could put one of the stations in a location to resolve the connection issues.

matt216 · Dec 8, 2020, 2:14 PM

Little update… upgraded the ‘flaky’ hotspot and ran an ethernet cable to it, rather than use powerline adapters. The mirror has held connection to the queue for 3 days now, which is by far a record!
Network connectivity seemed to be the issue, prompting a DNS error. Curious if the module could be a bit more resilient but perhaps that’s the nature of MQTT…? Decent home network has resolved.
Thanks for assistance.

sdetweil · Dec 8, 2020, 2:37 PM

@matt216 the code could be made more resilient, but maybe lower down than module, which module author doesn’t control.

Its hard to make 100% reliable code.

Glad u resolved to issue