By default at least on Centos 7 nfs only allows 8 connections and starts 8 nfsd daemons.
To fix this edit this file:/etc/sysconfig/nfs
Edit the line "RPCNFSDCOUNT" (uncomment it so it looks like this:
RPCNFSDCOUNT=30
In the example above we are setting 30 nfsd daemons to run (or in other words 30 connections are possible this way).........
Install Errors on Version 12:
This error happened on QEMU emulator version 2.11.1 pve-qemu-kvm_2.11.1-5
on Proxmox/Debian but installing on QEMU.12 on Centos 6 did not produce the error.
*Update it is not related to the OS or QEMU version. This happened in Centos 6 too after a second install.
What really causes this even though you successfully install........
This happens because Dovecot limits the maximum IMAPconnections per IPto just 10. This may be fine for a single client side IPbut if an entire office or multiple users are behind one IPor a single heavy user is active then you will get bizarre errors in your e-mail clients such as "Password Incorrect" or similar in Thunderbird. It won't be obvious on the client side as to what the problem is and they will probably just think the server is misconfi........