Sunfish and Raspbian GNU/Linux 12 (bookworm)

I have just spent the last four or so hours getting this to work, so this may just save somebody else some time.

Eventually I discovered that the syntax of the /etc/exports file has changed.
In the past you might have a line like this:

/ 192.168.9.*(rw,no_root_squash,async,no_subtree_check)

With Bookworm nothing can mount with this, from a linux machine you will get the following error, Sunfish will just time out:
mount.nfs: access denied by server while mounting 192.168.9.94:/

They seem to have changed to the CIDR /netmask notation and you have to change the export line like this:

/ 192.168.9.0/24(rw,no_root_squash,async,no_subtree_check)

I also found people saying to check your /etc/nfs.conf and make sure udp=y
I did this though I think sunfish will use tcp, older Acorn nfs clients may not and would need this.

I also did this:

chmod +rx /

may or may not have been necessary, I think I had to do this on the last pi where I tried to export /
but it was also the earlier version Raspbian GNU/Linux 11 (bullseye)

I’ve always used the second format, and it works with SunFish.

I’ve always used the second format, and it works with SunFish

I was curious, so I threw a query for each one at Google.
CIDR format turns up in items dating back to 2006, the first format doesn’t turn up at all, although I think, even back in the early 2000s use of the hostname might have been more common than using the IP in any format (CIDR or otherwise).