Troubleshooting OPC-UA connections

common connection issues error what it means how to fix no tcp connection network/firewall issue check network path and firewall windows test netconnection \<ip> port \<port> linux telnet \<ip> \<port> statusbadtcpendpointurlinvalid (0x80830000) wrong endpoint address check and correct the endpoint in server vs client failed to find suitable endpoint security settings mismatch adjust securitymode/policy in client or server statusbadidentitytokeninvalid (0x80200000) wrong username/password or credentials not needed enter correct credentials, or remove them if not needed eof / badsecuritychecksfailed (0x80130000) certificate not accepted yet accept the client certificate on the server other connection issues time difference if clocks are too much out of sync (hours, not seconds), security tokens may expire too soon sync all clocks with ntp common opc ua status codes when collecting data from an opc ua server, each value comes with a status code that tells you if the data is reliable (good) or if there is a problem with it here are some common status codes and what they mean status code meaning what to do bad (0x80000000) unspecified issue with the data check the data at the source badnodeidunknown (0x80340000) the nodeid is unknown to the server browse the server to find the correct nodeid badnodeidunknown (0x80340000), but only for monitored data the namespace is incorrect try another namespace, e g ns=2 instead of ns=3 or vice versa badtoomanyoperations (0x80100000) too many operations in one request lower the maxnodesperregister and/or maxnodesperread setting badtoomanymonitoreditems (0x80db0000) too many monitored items for the server adjust server limits or split over multiple collectors sometimes clean up old sessions goodoverload (0x002f0000) server can't keep up with requested rate lower the update rate or increase server resources badtimeout (0x800a0000) server couldn't provide a value in time check network, device status and server resources for a full list of opc ua status codes, see the https //github com/opcfoundation/ua nodeset/blob/latest/schema/statuscode csv factry status codes factry has added a few of our own status codes to highlight specific issues status code meaning what to do badinvalidnodeid the nodeid in your settings contains syntax errors enter a valid nodeid badfactryopcuaregisternodesfailed collector failed to register nodes (often too many at once) lower the maxnodesperregister and/or maxnodesperread setting badfactrymonitorerror / error from subscription notification channel collector failed to monitor nodes (often too many at once) lower the maxnodespermonitor setting badnovalueatarrayindex array index out of bounds or missing value check the arrayindex setting badfactryopcuatoomanyopenreadrequests new read requests open faster than they are processed check network, device status and server resources unknownstatuscode 0xxxx status code outside opc ua spec check server docs badfactryinvaliddatafordatatype data can't be parsed to the requested type check the datatype setting other data collection issues value for monitored measurement after reconnect whether monitored measurements receive a value after a reconnect depends on the implementation of the opc ua server there are 3 options the server does not send a value the server sends the latest value with its original timestamp the server sends the latest value with the current timestamp depending on the behaviour, a monitored measurement can keep a bad quality for a while after reconnect since the quality is only updated when points come in, the bad quality will remain until new good data arrives x509 invalid basic constraints the log error attempting to reconnect to opc ua server x509 invalid basic constraints indicates that the opc ua server certificate is not valid please contact your opc ua server vendor to update the server certificate to a valid one kepware for issues specific to kepware, have a look at docid\ b5nu0jekqrohmcg7xfu3c low level debugging if necessary, docid\ hcprrbdf014cy4o9r3w1i can be enabled to debug connection issues