NFS: доступ запрещен сервером при монтировании. стороной клиента является LXC proxmox (!)

извините, если эта тема копирует некоторые другие темы, но я не могу найти ответ в них.

что делает я имею:

сервером является Ubuntu 14.04.5 LTS

клиентом является Ubuntu 14.04.2 LTS - который является proxmox LXC

#cat /etc/exports

/nfs        192.168.88.0/24(ro,fsid=0,insecure,no_root_squash,no_subtree_check,sync)
/nfs/keycdn 192.168.88.0/24(rw,nohide,insecure,no_root_squash,no_subtree_check,sync)

Если я выполняю эту команду с сервера:

mount 192.168.88.185:/nfs/keycdn /mnt

Это смонтировано, и работа - я могу создать файл

Если я работаю на стороне клиента, я получаю ошибку:

root@kafka-02:/# mount 192.168.88.185:/nfs/keycdn /mnt
mount.nfs: access denied by server while mounting 192.168.88.185:/nfs/keycdn

Я имею такие права на папке: сервер

#ll /nfs/
drwxrwxrwx  3 nobody nogroup 4096 Mar 27 13:49 ./
drwxr-xr-x 24 root   root    4096 Mar 27 12:41 ../
drwxrwxrwx  2 nobody nogroup 4096 Mar 27 15:17 keycdn/

Для создания эффекта после изменения/etc/exports, я выполнил exportfs-rav и сервисный перезапуск сервера ядра nfs

Я попробовал, определяют стих nfs в/etc/fstab на стороне клиента. но никакой эффект

Там являются подробными на рабочей команде монтирования на сервере и клиенте:

Сервер

mount -vvvvvv 192.168.88.185:/nfs/keycdn /mnt
mount: fstab path: "/etc/fstab"
mount: mtab path:  "/etc/mtab"
mount: lock path:  "/etc/mtab~"
mount: temp path:  "/etc/mtab.tmp"
mount: UID:        0
mount: eUID:       0
mount: no type was given - I'll assume nfs because of the colon
mount: spec:  "192.168.88.185:/nfs/keycdn"
mount: node:  "/mnt"
mount: types: "nfs"
mount: opts:  "(null)"
mount: external mount: argv[0] = "/sbin/mount.nfs"
mount: external mount: argv[1] = "192.168.88.185:/nfs/keycdn"
mount: external mount: argv[2] = "/mnt"
mount: external mount: argv[3] = "-v"
mount: external mount: argv[4] = "-o"
mount: external mount: argv[5] = "rw"
mount.nfs: timeout set for Mon Mar 27 15:51:33 2017
mount.nfs: trying text-based options 'vers=4,addr=192.168.88.185,clientaddr=192.168.88.185'
mount.nfs: mount(2): No such file or directory
mount.nfs: trying text-based options 'addr=192.168.88.185'
mount.nfs: prog 100003, trying vers=3, prot=6
mount.nfs: trying 192.168.88.185 prog 100003 vers 3 prot TCP port 2049
mount.nfs: prog 100005, trying vers=3, prot=17
mount.nfs: trying 192.168.88.185 prog 100005 vers 3 prot UDP port 34598

Клиент vers=3

mount -o 'vers=3' -vvvvvvv 192.168.88.185:/nfs/keycdn /mnt
mount: fstab path: "/etc/fstab"
mount: mtab path:  "/etc/mtab"
mount: lock path:  "/etc/mtab~"
mount: temp path:  "/etc/mtab.tmp"
mount: UID:        0
mount: eUID:       0
mount: no type was given - I'll assume nfs because of the colon
mount: spec:  "192.168.88.185:/nfs/keycdn"
mount: node:  "/mnt"
mount: types: "nfs"
mount: opts:  "vers=3"
mount: external mount: argv[0] = "/sbin/mount.nfs"
mount: external mount: argv[1] = "192.168.88.185:/nfs/keycdn"
mount: external mount: argv[2] = "/mnt"
mount: external mount: argv[3] = "-v"
mount: external mount: argv[4] = "-o"
mount: external mount: argv[5] = "rw,vers=3"
mount.nfs: timeout set for Mon Mar 27 15:52:32 2017
mount.nfs: trying text-based options 'vers=3,addr=192.168.88.185'
mount.nfs: prog 100003, trying vers=3, prot=6
mount.nfs: trying 192.168.88.185 prog 100003 vers 3 prot TCP port 2049
mount.nfs: prog 100005, trying vers=3, prot=17
mount.nfs: trying 192.168.88.185 prog 100005 vers 3 prot UDP port 34598
mount.nfs: mount(2): Permission denied
mount.nfs: access denied by server while mounting 192.168.88.185:/nfs/keycdn

vers=4

mount -o 'vers=4' -vvvvvvv 192.168.88.185:/nfs/keycdn /mnt
mount: fstab path: "/etc/fstab"
mount: mtab path:  "/etc/mtab"
mount: lock path:  "/etc/mtab~"
mount: temp path:  "/etc/mtab.tmp"
mount: UID:        0
mount: eUID:       0
mount: no type was given - I'll assume nfs because of the colon
mount: spec:  "192.168.88.185:/nfs/keycdn"
mount: node:  "/mnt"
mount: types: "nfs"
mount: opts:  "vers=4"
mount: external mount: argv[0] = "/sbin/mount.nfs"
mount: external mount: argv[1] = "192.168.88.185:/nfs/keycdn"
mount: external mount: argv[2] = "/mnt"
mount: external mount: argv[3] = "-v"
mount: external mount: argv[4] = "-o"
mount: external mount: argv[5] = "rw,vers=4"
mount.nfs: timeout set for Mon Mar 27 15:56:55 2017
mount.nfs: trying text-based options 'vers=4,addr=192.168.88.185,clientaddr=192.168.88.252'
mount.nfs: mount(2): Permission denied
mount.nfs: access denied by server while mounting 192.168.88.185:/nfs/keycdn