vid=NaN (domain_sessionidx?)


As of 9/1 we’re seeing a sudden large volume of bad records with the error: Field [vid]: cannot convert [NaN] to Int

I believe this is the domain_sessionidx value?

We are still using JS tracker v2.6.2, no change there. Was there a change in certain browser functionality on that date that might affect this value somehow? (Just a shot in the dark, I know this value is derived from the user cookie.) Any other ideas on how this value could come back NaN?

It’s not affecting all events, only <=10%.

I am also seeing duid=value= in the same bad records, again suggesting a cookie parsing issue?

Any ideas or corroboration appreciated.


Root cause was found, it was simply cookie code collision in a small part of the site that unfortunately propagates forward.


Thanks for sharing the answer @seanhall, much appreciated! When you get an issue like this, it’s worth checking JavaScript scripts and cookies for any collisions…