So had a really tough issue to figure out, when a client doing SQL queries from Branch to Hub. THe issue was the first authentication failed, but then the DB would hold creds in it and it would work afterward. Had this at all branches to 2 SQL servers in the hub.
Meraki said nothing is being logged so it's not them, but if I whilelisted the client it worked. I create a custom policy to try to figure out where is was being block, when I just added in an any any rule (and using all the other MX defaults) it worked.
Then I took out the P2P rule and country blocks from the MX and it worked. I then added back the country blocks and it still worked. When I added back the P2P it failed. So now I had the problem. In speaking with support my questions were why isn't this block in the logs, and what ports/protocols are the P2P blocks using.
Answers - Layer 7 blocks are not logged and we don't know the ports/protocols P2P uses as we just get the feeds.
My other questions is when I created the Policy I only allowed the firewall features permit any any so the layer 7 rules still should have kicked in and blocked P2P, but they didn't . So now I think there are some bugs going on here, but why not log any blocks?