Cross Device Stitching - MCID missing in the URL

[Joachimsch]

We are experiencing an issue with our Cross Device Stitching. 2% of our occurrences where the Cross Device Stitching is expected, the MCMID is not included.

We expect the string to be:

MCMID=84899843812994052153346158800295853745|MCORGID=9D193D565A0AFF4XXXXX%40AdobeOrg|TS=173191117

But in some rare cases (2%) the string looks like this:

MCORGID=9D193D565A0AFF4XXXXX%40AdobeOrg|TS=173192890

Our implementation is not native app. Because we are using Tealium SDK that runs through a webview (embedded browser) to run the appMeasurement, that implementation is the only way of how we can asure that the cross device stitching is running.

The tricky part about our error, is that in 98% of all the cases, the function is running perfect. So we know it works. What surprises me is that MCID is completely missing from the string, while the rest is present (MCORGID and TS). On another note, this seems to only occur on iOS as well.

We append the MCID by using the Visitor.getInstance and .appendVisitorIDsTo functions and then do a sort of cutting and pasting to end up generating the expected URL with the adobe_mc query containing MCMID, MCORGID and Timestamp:

www.domain.com?adobe_mc=MCMID=xxxx|MCORGID=yyyyy|TS=zzzzz

Has anyone expected this behaviour before and also primarily on iOS?

[bjoern__koth]

The MCMID contains the ECID. Can you validate that the s_ecid cookie is present in those cases where the functionality does not work?

[Joachimsch]

Hi Björn

Thanks for taking your time to answer. 

Tried to validate if the ECID is present in all the hits, and it looks like our Experience Cloud ID coverage is 100% in all the cases.

We see different peaks over the last 12 months;

We cannot find a correlation or connection between these peaks and releases in Tealium or the app as well.

[Jennifer_Dungan]

Can you find any pattern to where the MCMID is missing from the URLs? Maybe coming from specific domains, or using specific OS/Browsers/etc. Anything you can find to try and do manual testing to try and replicate the scenario where it fails?

Do any of your sites have Cookie Opt-In/Out that you aren't setting an ECID for opt-outs? I.e. could Domain A be opted out, but Domain B be opted in, leading to Domain A not attaching the MCMID to the URL for Domain B? When Domain B loads, it generates a new ECID (since none is passed), so it would still look like 100% of traffic has an ECID?