<![CDATA[Bad file descriptor?]]>I frequently get the following error on a Modbus IP data source:

'polecat1ADAM': Exception from modbus master: Bad file descriptor (ioctl FIONREAD failed)

Any suggestions?

]]>https://forum.mango-os.com/topic/4328/bad-file-descriptorRSS for NodeThu, 14 May 2026 16:25:40 GMTMon, 22 Jul 2019 19:13:03 GMT60<![CDATA[Reply to Bad file descriptor? on Tue, 23 Jul 2019 16:51:14 GMT]]>Mango is on the same LAN with the Modbus IP devices.

I was using TCP, and have switched to TCP with keepalive to see if that helps.

]]>https://forum.mango-os.com/post/22812https://forum.mango-os.com/post/22812Tue, 23 Jul 2019 16:51:14 GMT<![CDATA[Reply to Bad file descriptor? on Tue, 23 Jul 2019 16:18:19 GMT]]>Hi pyeager,

Someone else encountered this message in this thread: https://forum.infiniteautomation.com/topic/3360/urgent-alarm-identification

And persuaded themselves it had to do with the spottiness of the internet connection they were polling. Are you using TCP with keep alive, or just TCP?

]]>https://forum.mango-os.com/post/22811https://forum.mango-os.com/post/22811Tue, 23 Jul 2019 16:18:19 GMT