We run this successfully, although some discrepancy in the data is always a problem. However, since the second level cache is configured for each site, you can disable it, as well as disable it for certain areas of the cache on your manager.
The second level cache will be read-only, since explicit updates will be flushed and saved directly.
, "" , - , . NHibernate , .
, concurrency , . , -:
Site will create orders, modify customers etc but only read products, prices and categories
Admin will modify orders, products, prices and categories but only read customers
NHibernate / , concurrency = "true" . , concurrency.