# service nfs restart
Shutting down NFS daemon: [ OK ]
Shutting down NFS mountd: [ OK ]
Shutting down NFS quotas: [FAILED]
Shutting down NFS services: [ OK ]
Shutting down RPC idmapd: [ OK ]
Starting NFS services: [ OK ]
Starting NFS quotas: Cannot register service: RPC: Authentication error; why = Client credential too weak
rpc.rquotad: unable to register (RQUOTAPROG, RQUOTAVERS, udp).
Вот такая ошибка при старте NFS. Quota нужны. Стоит CentOS 6 x86_64.