我有一台 FreeNAS (9.10-STABLE-201605240427 ) 服务器和几个 CentOS 6.4 机器。然而，CentOS 机器似乎无法写入 FreeNAS 挂载任何大于 4KB 的文件，无论它们是使用 CIFS 还是 NFS（3 和 4）挂载。
由于某些奇怪的原因，每当您尝试写入大于 4KB（页面大小）的文件时，似乎都会出现某种死锁。
这是当我尝试将 /bin/ls 复制到挂载时，来自 CentOS 计算机的 NFS 调试日志的摘录。
Sep 2 22:13:20 RAX-NERVE kernel: NFS: nfs_update_inode(0:17/4 fh_crc=0x2877d5c3 ct=2 info=0x227e7f)
Sep 2 22:13:20 RAX-NERVE kernel: NFS: permission(0:17/4), mask=0x1, res=0
Sep 2 22:13:20 RAX-NERVE kernel: NFS: atomic_lookup(0:17/4), ls
Sep 2 22:13:20 RAX-NERVE kernel: NFS: lookup(/ls)
Sep 2 22:13:20 RAX-NERVE kernel: NFS call lookup ls
Sep 2 22:13:20 RAX-NERVE kernel: encode_compound: tag=
Sep 2 22:13:20 RAX-NERVE kernel: decode_attr_type: type=0100000
Sep 2 22:13:20 RAX-NERVE kernel: decode_attr_change: change attribute=8013396
Sep 2 22:13:20 RAX-NERVE kernel: decode_attr_size: file size=0
Sep 2 22:13:20 RAX-NERVE kernel: decode_attr_fsid: fsid=(0x76431d7a/0x9cf9cdde)
Sep 2 22:13:20 RAX-NERVE kernel: decode_attr_fileid: fileid=41
Sep 2 22:13:20 RAX-NERVE kernel: decode_attr_fs_locations: fs_locations done, error = 0
Sep 2 22:13:20 RAX-NERVE kernel: decode_attr_mode: file mode=0775
Sep 2 22:13:20 RAX-NERVE kernel: decode_attr_nlink: nlink=1
Sep 2 22:13:20 RAX-NERVE kernel: decode_attr_owner: uid=99
Sep 2 22:13:20 RAX-NERVE kernel: decode_attr_group: gid=99
Sep 2 22:13:20 RAX-NERVE kernel: decode_attr_rdev: rdev=(0x3:0xc7)
Sep 2 22:13:20 RAX-NERVE kernel: decode_attr_space_used: space used=512
Sep 2 22:13:20 RAX-NERVE kernel: decode_attr_time_access: atime=502412
Sep 2 22:13:20 RAX-NERVE kernel: decode_attr_time_metadata: ctime=1472850295
Sep 2 22:13:20 RAX-NERVE kernel: decode_attr_time_modify: mtime=1472850295
Sep 2 22:13:20 RAX-NERVE kernel: decode_attr_mounted_on_fileid: fileid=41
Sep 2 22:13:20 RAX-NERVE kernel: decode_getfattr_attrs: xdr returned -2097152
Sep 2 22:13:20 RAX-NERVE kernel: decode_getfattr_generic: xdr returned 0
Sep 2 22:13:20 RAX-NERVE kernel: NFS reply lookup: 0
Sep 2 22:13:20 RAX-NERVE kernel: NFS: nfs_fhget(0:17/41 fh_crc=0x2947d423 ct=1)
Sep 2 22:13:20 RAX-NERVE kernel: NFS: dentry_delete(/ls, 0)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: permission(0:17/4), mask=0x1, res=0
Sep 2 22:13:21 RAX-NERVE kernel: --> nfs_put_client({2})
Sep 2 22:13:21 RAX-NERVE kernel: encode_compound: tag=
Sep 2 22:13:21 RAX-NERVE kernel: encode_compound: tag=
Sep 2 22:13:21 RAX-NERVE kernel: nfs4_schedule_state_renewal: requeueing work. Lease period = 48
Sep 2 22:13:21 RAX-NERVE kernel: --> nfs_put_client({3})
Sep 2 22:13:21 RAX-NERVE kernel: --> nfs_put_client({2})
Sep 2 22:13:21 RAX-NERVE kernel: <-- nfs4_setup_sequence status=0
Sep 2 22:13:21 RAX-NERVE kernel: encode_compound: tag=
Sep 2 22:13:21 RAX-NERVE kernel: decode_attr_type: type=0100000
Sep 2 22:13:21 RAX-NERVE kernel: decode_attr_change: change attribute=8013396
Sep 2 22:13:21 RAX-NERVE kernel: decode_attr_size: file size=0
Sep 2 22:13:21 RAX-NERVE kernel: decode_attr_fsid: fsid=(0x76431d7a/0x9cf9cdde)
Sep 2 22:13:21 RAX-NERVE kernel: decode_attr_fileid: fileid=41
Sep 2 22:13:21 RAX-NERVE kernel: decode_attr_fs_locations: fs_locations done, error = 0
Sep 2 22:13:21 RAX-NERVE kernel: decode_attr_mode: file mode=0775
Sep 2 22:13:21 RAX-NERVE kernel: decode_attr_nlink: nlink=1
Sep 2 22:13:21 RAX-NERVE kernel: decode_attr_owner: uid=-2
Sep 2 22:13:21 RAX-NERVE kernel: decode_attr_group: gid=-2
Sep 2 22:13:21 RAX-NERVE kernel: decode_attr_rdev: rdev=(0x3:0xc7)
Sep 2 22:13:21 RAX-NERVE kernel: decode_attr_space_used: space used=512
Sep 2 22:13:21 RAX-NERVE kernel: decode_attr_time_access: atime=502412
Sep 2 22:13:21 RAX-NERVE kernel: decode_attr_time_metadata: ctime=1472850295
Sep 2 22:13:21 RAX-NERVE kernel: decode_attr_time_modify: mtime=1472850295
Sep 2 22:13:21 RAX-NERVE kernel: decode_attr_mounted_on_fileid: fileid=41
Sep 2 22:13:21 RAX-NERVE kernel: decode_getfattr_attrs: xdr returned -2097152
Sep 2 22:13:21 RAX-NERVE kernel: decode_getfattr_generic: xdr returned 0
Sep 2 22:13:21 RAX-NERVE kernel: encode_compound: tag=
Sep 2 22:13:21 RAX-NERVE kernel: NFS: nfs_update_inode(0:17/41 fh_crc=0x2947d423 ct=3 info=0x227e7f)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: nfs_fhget(0:17/41 fh_crc=0x2947d423 ct=3)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: nfsi 0xffff880117664930 disabling cache
Sep 2 22:13:21 RAX-NERVE kernel: NFS: permission(0:17/41), mask=0x22, res=0
Sep 2 22:13:21 RAX-NERVE kernel: NFS: write(/ls, 109208@0)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: write_begin(/ls(41), 4096@0)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: write_end(/ls(41), 4096@0)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: nfs_updatepage(/ls 4096@0)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: nfs_updatepage returns 0 (isize 4096)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: write_begin(/ls(41), 4096@4096)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: write_end(/ls(41), 4096@4096)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: nfs_updatepage(/ls 4096@4096)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: nfs_updatepage returns 0 (isize 8192)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: write_begin(/ls(41), 4096@8192)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: write_end(/ls(41), 4096@8192)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: nfs_updatepage(/ls 4096@8192)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: nfs_updatepage returns 0 (isize 12288)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: write_begin(/ls(41), 4096@12288)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: write_end(/ls(41), 4096@12288)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: nfs_updatepage(/ls 4096@12288)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: nfs_updatepage returns 0 (isize 16384)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: write_begin(/ls(41), 4096@16384)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: write_end(/ls(41), 4096@16384)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: nfs_updatepage(/ls 4096@16384)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: nfs_updatepage returns 0 (isize 20480)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: write_begin(/ls(41), 4096@20480)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: write_end(/ls(41), 4096@20480)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: nfs_updatepage(/ls 4096@20480)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: nfs_updatepage returns 0 (isize 24576)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: write_begin(/ls(41), 4096@24576)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: write_end(/ls(41), 4096@24576)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: nfs_updatepage(/ls 4096@24576)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: nfs_updatepage returns 0 (isize 28672)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: write_begin(/ls(41), 4096@28672)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: write_end(/ls(41), 4096@28672)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: nfs_updatepage(/ls 4096@28672)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: nfs_updatepage returns 0 (isize 32768)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: write_begin(/ls(41), 4096@32768)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: write_end(/ls(41), 4096@32768)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: nfs_updatepage(/ls 4096@32768)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: nfs_updatepage returns 0 (isize 36864)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: write_begin(/ls(41), 4096@36864)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: write_end(/ls(41), 4096@36864)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: nfs_updatepage(/ls 4096@36864)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: nfs_updatepage returns 0 (isize 40960)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: write_begin(/ls(41), 4096@40960)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: write_end(/ls(41), 4096@40960)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: nfs_updatepage(/ls 4096@40960)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: nfs_updatepage returns 0 (isize 45056)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: write_begin(/ls(41), 4096@45056)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: write_end(/ls(41), 4096@45056)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: nfs_updatepage(/ls 4096@45056)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: nfs_updatepage returns 0 (isize 49152)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: write_begin(/ls(41), 4096@49152)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: write_end(/ls(41), 4096@49152)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: nfs_updatepage(/ls 4096@49152)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: nfs_updatepage returns 0 (isize 53248)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: write_begin(/ls(41), 4096@53248)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: write_end(/ls(41), 4096@53248)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: nfs_updatepage(/ls 4096@53248)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: nfs_updatepage returns 0 (isize 57344)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: write_begin(/ls(41), 4096@57344)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: write_end(/ls(41), 4096@57344)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: nfs_updatepage(/ls 4096@57344)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: nfs_updatepage returns 0 (isize 61440)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: write_begin(/ls(41), 4096@61440)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: write_end(/ls(41), 4096@61440)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: nfs_updatepage(/ls 4096@61440)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: nfs_updatepage returns 0 (isize 65536)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: write_begin(/ls(41), 4096@65536)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: write_end(/ls(41), 4096@65536)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: nfs_updatepage(/ls 4096@65536)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: nfs_updatepage returns 0 (isize 69632)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: write_begin(/ls(41), 4096@69632)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: write_end(/ls(41), 4096@69632)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: nfs_updatepage(/ls 4096@69632)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: nfs_updatepage returns 0 (isize 73728)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: write_begin(/ls(41), 4096@73728)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: write_end(/ls(41), 4096@73728)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: nfs_updatepage(/ls 4096@73728)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: nfs_updatepage returns 0 (isize 77824)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: write_begin(/ls(41), 4096@77824)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: write_end(/ls(41), 4096@77824)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: nfs_updatepage(/ls 4096@77824)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: nfs_updatepage returns 0 (isize 81920)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: write_begin(/ls(41), 4096@81920)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: write_end(/ls(41), 4096@81920)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: nfs_updatepage(/ls 4096@81920)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: nfs_updatepage returns 0 (isize 86016)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: write_begin(/ls(41), 4096@86016)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: write_end(/ls(41), 4096@86016)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: nfs_updatepage(/ls 4096@86016)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: nfs_updatepage returns 0 (isize 90112)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: write_begin(/ls(41), 4096@90112)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: write_end(/ls(41), 4096@90112)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: nfs_updatepage(/ls 4096@90112)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: nfs_updatepage returns 0 (isize 94208)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: write_begin(/ls(41), 4096@94208)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: write_end(/ls(41), 4096@94208)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: nfs_updatepage(/ls 4096@94208)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: nfs_updatepage returns 0 (isize 98304)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: write_begin(/ls(41), 4096@98304)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: write_end(/ls(41), 4096@98304)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: nfs_updatepage(/ls 4096@98304)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: nfs_updatepage returns 0 (isize 102400)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: write_begin(/ls(41), 4096@102400)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: write_end(/ls(41), 4096@102400)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: nfs_updatepage(/ls 4096@102400)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: nfs_updatepage returns 0 (isize 106496)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: write_begin(/ls(41), 2712@106496)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: write_end(/ls(41), 2712@106496)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: nfs_updatepage(/ls 2712@106496)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: nfs_updatepage returns 0 (isize 109208)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: flush(/ls)
Sep 2 22:13:21 RAX-NERVE kernel: NFS: 0 initiated write call (req 0:17/41, 109208 bytes @ offset 0)
Sep 2 22:13:21 RAX-NERVE kernel: <-- nfs4_setup_sequence status=0
Sep 2 22:13:21 RAX-NERVE kernel: encode_compound: tag=
Sep 2 22:14:09 RAX-NERVE kernel: nfs4_renew_state: start
Sep 2 22:14:09 RAX-NERVE kernel: nfs4_renew_state: done
Sep 2 22:15:33 RAX-NERVE kernel: INFO: task cp:2850 blocked for more than 120 seconds.
Sep 2 22:15:33 RAX-NERVE kernel: Not tainted 2.6.32-642.4.2.el6.x86_64 #1
Sep 2 22:15:33 RAX-NERVE kernel: "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
Sep 2 22:15:33 RAX-NERVE kernel: cp D 0000000000000003 0 2850 2296 0x00000080
Sep 2 22:15:33 RAX-NERVE kernel: ffff88012c3afc78 0000000000000082 ffff88012c3afbc8 ffffffffa051b3ee
Sep 2 22:15:33 RAX-NERVE kernel: ffff88012c3afbf8 ffffffffa051bc90 ffff88012c3afbe8 ffff88012c3afc28
Sep 2 22:15:33 RAX-NERVE kernel: ffff88012c77bc70 ffff880117664af8 ffff88012798fad8 ffff88012c3affd8
Sep 2 22:15:33 RAX-NERVE kernel: Call Trace:
Sep 2 22:15:33 RAX-NERVE kernel: [<ffffffffa051b3ee>] ? rpc_make_runnable+0x7e/0x80 [sunrpc]
Sep 2 22:15:33 RAX-NERVE kernel: [<ffffffffa051bc90>] ? rpc_execute+0x50/0xa0 [sunrpc]
Sep 2 22:15:33 RAX-NERVE kernel: [<ffffffff8112e3f0>] ? sync_page+0x0/0x50
Sep 2 22:15:33 RAX-NERVE kernel: [<ffffffff81549163>] io_schedule+0x73/0xc0
Sep 2 22:15:33 RAX-NERVE kernel: [<ffffffff8112e42d>] sync_page+0x3d/0x50
Sep 2 22:15:33 RAX-NERVE kernel: [<ffffffff81549c4f>] __wait_on_bit+0x5f/0x90
Sep 2 22:15:33 RAX-NERVE kernel: [<ffffffff8112e663>] wait_on_page_bit+0x73/0x80
Sep 2 22:15:33 RAX-NERVE kernel: [<ffffffff810a6920>] ? wake_bit_function+0x0/0x50
Sep 2 22:15:33 RAX-NERVE kernel: [<ffffffff811447a5>] ? pagevec_lookup_tag+0x25/0x40
Sep 2 22:15:33 RAX-NERVE kernel: [<ffffffff8112ea8b>] wait_on_page_writeback_range+0xfb/0x190
Sep 2 22:15:33 RAX-NERVE kernel: [<ffffffff8112ec58>] filemap_write_and_wait_range+0x78/0x90
Sep 2 22:15:33 RAX-NERVE kernel: [<ffffffff811cc92e>] vfs_fsync_range+0x7e/0x100
Sep 2 22:15:33 RAX-NERVE kernel: [<ffffffff811cca1d>] vfs_fsync+0x1d/0x20
Sep 2 22:15:33 RAX-NERVE kernel: [<ffffffffa05bb9e0>] nfs_file_flush+0x70/0xa0 [nfs]
Sep 2 22:15:33 RAX-NERVE kernel: [<ffffffff811967fc>] filp_close+0x3c/0x90
Sep 2 22:15:33 RAX-NERVE kernel: [<ffffffff811968f5>] sys_close+0xa5/0x100
Sep 2 22:15:33 RAX-NERVE kernel: [<ffffffff8100b0d2>] system_call_fastpath+0x16/0x1b
我完全不知道是什么原因造成的。 Windows 和 OS X 客户端都可以毫无问题地挂载和读取/写入这些分区。这些设备直接插入同一台交换机，除了 VLAN 标记/虚拟接口之外，网络根本没有理由出现故障。
能够在 Ubuntu 机器上复制该问题，所以我认为故障出在 FreeNAS 服务器本身，但重新安装并没有解决问题。
答案1
设法解决了它。
FreeNAS 默认设置的 MTU 为 9000，网卡不支持该设置。因此，可能会丢弃一堆数据包，从而导致挂起。
修复方法是将“mtu 1400”添加到网络接口设置中。
这是一个网络问题。希望这对处于相同位置的人有所帮助。