嵌入式NFS服务器不支持ver=2，但支持1,3 -这可能吗？

Question

我来自MontaVista的2.6.37Linux已经编译了NFS模块。我从以下顺序开始：

rpcbind
rpc.nfsd 4
rpc.mountd
rpc.statd

使用默认配置文件和etab，如：

/mnt/sda1 192.168.50.0/24(rw,sync,wdelay,hide,nocrossmnt,secure,no_root_squash,no_all_squash,no_subtree_check,secure_locks,acl,fsid=1,anonuid=65534,anongid=65534)

作为客户端，我的FC32一切都很好：

[root@leonp mnt]# mount -v 192.168.1.1:/mnt/sda1/ srv
mount.nfs: timeout set for Mon Aug  3 16:04:08 2020
mount.nfs: trying text-based options 'vers=4.2,addr=192.168.1.1,clientaddr=192.168.1.57'
mount.nfs: mount(2): Protocol not supported
mount.nfs: trying text-based options 'vers=4,minorversion=1,addr=192.168.1.1,clientaddr=192.168.1.57'
mount.nfs: mount(2): Protocol not supported
mount.nfs: trying text-based options 'vers=4,addr=192.168.1.1,clientaddr=192.168.1.57'
mount.nfs: mount(2): Protocol not supported
mount.nfs: trying text-based options 'addr=192.168.1.1'
mount.nfs: prog 100003, trying vers=3, prot=6
mount.nfs: trying 192.168.1.1 prog 100003 vers 3 prot TCP port 2049
mount.nfs: prog 100005, trying vers=3, prot=17
mount.nfs: trying 192.168.1.1 prog 100005 vers 3 prot UDP port 39445
[root@leonp mnt]#

当我试图连接只支持NFSv2的客户端时，问题就开始了。因此，要在PC上进行测试：

[root@leonp mnt]# mount -vvv -o vers=2 192.168.1.1:/mnt/sda1/ srv
mount.nfs: timeout set for Mon Aug  3 13:50:14 2020
mount.nfs: trying text-based options 'vers=2,addr=192.168.1.1'
mount.nfs: prog 100003, trying vers=2, prot=6
mount.nfs: trying 192.168.1.1 prog 100003 vers 2 prot TCP port 2049
mount.nfs: prog 100005, trying vers=1, prot=17
mount.nfs: trying 192.168.1.1 prog 100005 vers 1 prot UDP port 36357
mount.nfs: mount(2): Protocol not supported
mount.nfs: Protocol not supported

为什么要这样？我查过：

[root@leonp mnt]# rpcinfo 192.168.1.1 
   program version netid     address                service    owner
    100000    4    tcp       0.0.0.0.0.111          portmapper superuser
    100000    3    tcp       0.0.0.0.0.111          portmapper superuser
    100000    2    tcp       0.0.0.0.0.111          portmapper superuser
    100000    4    udp       0.0.0.0.0.111          portmapper superuser
    100000    3    udp       0.0.0.0.0.111          portmapper superuser
    100000    2    udp       0.0.0.0.0.111          portmapper superuser
    100000    4    local     /var/run/rpcbind.sock  portmapper superuser
    100000    3    local     /var/run/rpcbind.sock  portmapper superuser
    100003    2    tcp       0.0.0.0.8.1            nfs        unknown
    100003    3    tcp       0.0.0.0.8.1            nfs        unknown
    100003    2    udp       0.0.0.0.8.1            nfs        unknown
    100003    3    udp       0.0.0.0.8.1            nfs        unknown
    100021    1    udp       0.0.0.0.148.56         nlockmgr   unknown
    100021    3    udp       0.0.0.0.148.56         nlockmgr   unknown
    100021    4    udp       0.0.0.0.148.56         nlockmgr   unknown
    100021    1    tcp       0.0.0.0.228.206        nlockmgr   unknown
    100021    3    tcp       0.0.0.0.228.206        nlockmgr   unknown
    100021    4    tcp       0.0.0.0.228.206        nlockmgr   unknown
    100005    1    udp       0.0.0.0.142.5          mountd     superuser
    100005    1    tcp       0.0.0.0.130.95         mountd     superuser
    100005    2    udp       0.0.0.0.218.108        mountd     superuser
    100005    2    tcp       0.0.0.0.174.251        mountd     superuser
    100005    3    udp       0.0.0.0.154.21         mountd     superuser
    100005    3    tcp       0.0.0.0.132.150        mountd     superuser

唯一不支持v2的是nlockmgr --它可能是拒绝安装的原因吗？为了测试这一点，我尝试从运行中删除nlockmgr --没有成功。我试图通过注释掉100021来阻止它在/etc/rpc中，但没有成功。

更新：

#rcp.nfsd -d
rpc.nfsd: Checking netconfig for visible protocols.
rpc.nfsd: Enabling inet udp.
rpc.nfsd: Enabling inet tcp.
rpc.nfsd: knfsd is currently down
rpc.nfsd: Writing version string to kernel: +4.1 +2 +3 +4

#cat /proc/fs/nfsd/versions
+2 +3
============

任何帮助都将不胜感激。

Answer 1

您需要调整NFS内核服务器以提供版本2(正如您已经注意到的，默认情况下它不再包括该版本)。在服务器上运行此程序将允许您测试建议的修补程序是否有效。

rpc.nfsd 0 && sleep 1           # Stop all previous threads
rpc.nfsd --nfs-version 2,3 8    # Restart 8 threads with versions 2 and 3

如果有效的话，你需要让它永久化。在我的Debian ("buster")系统上，似乎仍然需要编辑/etc/default/nfs-kernel-server。在您的系统中，可能会有所不同。

原码

# Number of servers to start up
RPCNFSDCOUNT=32

修正代码

# Options and number of servers to start up
RPCNFSDCOUNT='--nfs-version 2,3 8'