As the subject says, after applying the SUPEE-10415 patch, all seems fine until "redis-cli flushall" then we get the annoying "404 error: Page not found." on everything. After a process of elimination, disabling extensions as magento devdocs suggested, nothing seemed to change until we removed the cache tags from the local.xml file.
Curious if anyone has any "ah hah" idea why everything works fine without redis but 404s when it's enabled.
If it's any significance here is the code that I have that only works when removed from the local.xml after patching.
<cache> <backend>Mage_Cache_Backend_Redis</backend> <backend_options> <server>127.0.0.1</server> <port>6379</port> <persistent></persistent> <database>0</database> <password></password> <force_standalone>0</force_standalone> <connect_retries>1</connect_retries> <read_timeout>10</read_timeout> <automatic_cleaning_factor>0</automatic_cleaning_factor> <compress_data>1</compress_data> <compress_tags>1</compress_tags> <compress_threshold>20480</compress_threshold> <compression_lib>gzip</compression_lib> </backend_options> </cache>