SOLVED
So today after 4+ years of marketo-ing I learned something most everyone knows. Partially syncing MKTO <-> SFDC requires that Marketo support manually define your chosen "Marketing Sync" SFDC field in the marketo back-end system. This confused me since I thought that syncing was controlled by the rights the sfdc admin gives to the Sync User...
My Simplified Contemplation
1. Technically a Marketo Sync user in salesforce is just a user...
2. As a user, there are differing profiles, roles and permissions based on any number of things, i.e: regions, demographics etc.
3. Why must it go through a hard coded switch via marketo and not via the sfdc visibility rules
With that said: Wouldn't it be possible to set up SFDC in a way that enables Marketo to only see/edit specific records based on a field or value... ie: Marketing Sync Field: Sync Disabled | Sync Enabled?
I also uncovered today that when selective syncing (not 1:1), leads previously synced with sfdc that are later updated by mkto are not automatically synced back to/with sfdc in its recurring sync cycles... is that really true?
Maybe Greg could help 
1 ACCEPTED SOLUTION
Accepted Solutions
Hi David
I thought that syncing was controlled by the rights the sfdc admin gives to the Sync User
Well, this is still true 
Another consideration: SFDC profiles and Permission sets are of little help. Your profile has access to leads or not. The only thing that SFDC profiles or permission sets can do easily is to give access to all leads or all contacts through the "view all / edit all" right.
That leaves SFDC roles and sharing rules. These can be very helpful if for instance you plan to sync Marketo with the data from one business unit and leave the others aside. Field based sharing rules can also be useful to add some accuracy and fine tuning, of course. So using SFDC roles and sharing rules can be enough for your needs.
I prefer to use a sync field, though. The sync field has the advantage that it enables you more flexibility than SFDC roles and sharing rules. It also enables you to set rules that can be activated with workflows and/or process builders based on complex logic and make the whole system quite evolutive. We always set this with a specific, dedicated field. Let's name it "Sync With Marketo", type boolean. Never use a formula here, because you want to make sure that updates to that field is the result of an update to the record itself and will trigger a sync. There is also an hope that Marketo will some day enhance the support of the Sync field as proposed in a few of the ideas listed here:
Once the field is set, we usually setup workflows or business processes to have it populated. Once the field is populated, ask support to activate the sync filter and you are done.
So to answer your 1st question, yes, this is easy to do.
You can read these:
On your second question, I am not sure of what you are meaning here. if you have a sync filter enabled, only the records for which the filter is true will sync from Marketo to SFDC. On the contrary, if the sync is false, the sync stops immediately. This is described in the 2 blog articles above. The second provides a mechanism to manage unsync.
Also, sync'ed records will sync on a planned sync if they have been updated since the previous sync and only in this case.
-Greg
Hi David
I thought that syncing was controlled by the rights the sfdc admin gives to the Sync User
Well, this is still true
Another consideration: SFDC profiles and Permission sets are of little help. Your profile has access to leads or not. The only thing that SFDC profiles or permission sets can do easily is to give access to all leads or all contacts through the "view all / edit all" right.
That leaves SFDC roles and sharing rules. These can be very helpful if for instance you plan to sync Marketo with the data from one business unit and leave the others aside. Field based sharing rules can also be useful to add some accuracy and fine tuning, of course. So using SFDC roles and sharing rules can be enough for your needs.
I prefer to use a sync field, though. The sync field has the advantage that it enables you more flexibility than SFDC roles and sharing rules. It also enables you to set rules that can be activated with workflows and/or process builders based on complex logic and make the whole system quite evolutive. We always set this with a specific, dedicated field. Let's name it "Sync With Marketo", type boolean. Never use a formula here, because you want to make sure that updates to that field is the result of an update to the record itself and will trigger a sync. There is also an hope that Marketo will some day enhance the support of the Sync field as proposed in a few of the ideas listed here:
Once the field is set, we usually setup workflows or business processes to have it populated. Once the field is populated, ask support to activate the sync filter and you are done.
So to answer your 1st question, yes, this is easy to do.
You can read these:
On your second question, I am not sure of what you are meaning here. if you have a sync filter enabled, only the records for which the filter is true will sync from Marketo to SFDC. On the contrary, if the sync is false, the sync stops immediately. This is described in the 2 blog articles above. The second provides a mechanism to manage unsync.
Also, sync'ed records will sync on a planned sync if they have been updated since the previous sync and only in this case.
-Greg
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