我无法更新 NFS。自从我从 10.04 LTS 升级以来，更新管理器显示两个 NFS 包，但它不允许我单击它们。
我应该怎么办？
我试过：
sudo apt-get -oDebug::PkgProblemResolver=1 dist-upgrade
但它没有帮助，例如：
Reading package lists... Done
Building dependency tree
Reading state information... Done
Calculating upgrade... Starting
Starting 2
Investigating (0) rpcbind [ amd64 ] < none -> 0.2.0-7ubuntu1 > ( net )
Broken rpcbind:amd64 Conflicts on portmap [ amd64 ] < 6.0.0-1ubuntu2.2 > ( net )
Considering portmap:amd64 1 as a solution to rpcbind:amd64 1
Holding Back rpcbind:amd64 rather than change portmap:amd64
Investigating (0) nfs-common [ amd64 ] < 1:1.2.0-4ubuntu4.2 -> 1:1.2.5-3ubuntu3 > ( net )
Broken nfs-common:amd64 Depends on rpcbind [ amd64 ] < none -> 0.2.0-7ubuntu1 > ( net ) (>= 0.2.0-6ubuntu1)
Considering rpcbind:amd64 1 as a solution to nfs-common:amd64 1
Holding Back nfs-common:amd64 rather than change rpcbind:amd64
Investigating (0) nfs-kernel-server [ amd64 ] < 1:1.2.0-4ubuntu4.2 -> 1:1.2.5-3ubuntu3 > ( net )
Broken nfs-kernel-server:amd64 Depends on nfs-common [ amd64 ] < 1:1.2.0-4ubuntu4.2 -> 1:1.2.5-3ubuntu3 > ( net ) (= 1:1.2.5-3ubuntu3)
Considering nfs-common:amd64 1 as a solution to nfs-kernel-server:amd64 0
Holding Back nfs-kernel-server:amd64 rather than change nfs-common:amd64
Try to Re-Instate (1) nfs-common:amd64
Try to Re-Instate (1) nfs-kernel-server:amd64
Done
Done
The following packages have been kept back:
nfs-common nfs-kernel-server
0 upgraded, 0 newly installed, 0 to remove and 2 not upgraded.
我发现了一个错误报告与我的问题类似，但我不明白如何“将档案中的 rpcbind 优先级提升为‘标准’？”这是什么意思？有人能给我指出正确的方向吗？