I'm new to linux, I'm not dumb but please explain like I am. I had a problem earlier this morning that's fixed, but I don't understand why and am hoping someone can explain it.
I mount two shared folders from my NAS (Synology DSM 7.2) to my linux home server (Debian 12). As of last night, I had no problem mounting both NAS folders (call them folder1 and folder2) on the linux machine via nfs. Both folders have identical nfs permissions.
Sometime last night I had a power outage and because I had the linux machine connected directly with the wall to futz with it, it went down. This morning I booted it up and tried to mount both folders again:
mount -t nfs ###.###.###.###:/volume1/folder1 /mnt/folder1
Folder1 mounted just fine. With folder2, I got this guy:
mount.nfs: access denied by server while mounting ###:###:###:###:/volume1/folder2
With some googling, I changed nfs permissions for folder2 to allow a broader range of ip addresses, ###.###.0.0/16. That worked. But why would that matter? Both mount requests are coming from the same static ip. I'd hypothesize something about the one nfs connection blocking the other out, but that would seem to be ruled out from the fact that the former permissions, which accepted connections from the same ip, worked just fine yesterday. What's going on here?
Additional details:
I was expecting to mount both folders with identical permissions. For both, I originally had permissions enabled for the linux ip. Each allowed r/w access to the folder from that ip, with all users mapped to guest (yeah, I'll set up more fine-grained user permissions once I better understand things). The NAS nfs settings are enabled up to version 4.1, and I assume that's what Debian uses, though not sure.
I think this should be irrelevant, but I'd originally had some trouble reading and writing to the mounted folders from my docker containers, so on both folders from the NAS I changed the owner of the folder and all files recursively to 'guest', the account to which all nfs users are mapped, with 777 permissions. (There's nothing in these folders I can't afford to lose). That solved the r/w problem.