| 1 |
On Sat, Jul 26, 2014 at 9:51 AM, Alan McKinnon <alan.mckinnon@×××××.com> wrote: |
| 2 |
> |
| 3 |
> NFS uses RPC to do some heavy lifting - I don't know how familiar you |
| 4 |
> are with this, so here's the quick version: |
| 5 |
> |
| 6 |
> When you mount something locally, and need to use the mounted |
| 7 |
> filesystem, kernel calls are used to get at the data. This works easily |
| 8 |
> as the source disk is local and the kernel can get to it. With NFS, the |
| 9 |
> source disk is remote and it's the remote kernel that must do the |
| 10 |
> accessing. RPC is a way to safely ask a remote kernel to do something |
| 11 |
> and get a result that behaves identical to a local kernel call. |
| 12 |
> Obviously, this is rather hard to implement correctly. |
| 13 |
> |
| 14 |
> The original RPC was written by Sun and other newer implementations |
| 15 |
> exist, like libtirpc - to support useful features like not being stuck |
| 16 |
> with only UDP. That's what the "ti" means - Transport Independant. |
| 17 |
> |
| 18 |
> RPC has been in a state of flux for some time and I too have run into |
| 19 |
> init-script oddities as things change. |
| 20 |
> |
| 21 |
> In my case, I have nfs-utils-1.3.0, and rc-update configuredd to start |
| 22 |
> rpc.statd. This works because |
| 23 |
> |
| 24 |
> depend() { |
| 25 |
> ... |
| 26 |
> need portmap |
| 27 |
> ... |
| 28 |
> } |
| 29 |
> |
| 30 |
> and in the init.d file for rpcbind: |
| 31 |
> |
| 32 |
> depend() { |
| 33 |
> ... |
| 34 |
> provide portmap |
| 35 |
> } |
| 36 |
> |
| 37 |
> So rpcbind starts at boot time and all my nfs mounts JustWork |
| 38 |
|
| 39 |
To confirm the above, for nfs-utils-1.2.9-r3. |
| 40 |
|
| 41 |
If I start nfs manually, all the associated daemons start too even |
| 42 |
though I haven't added them to "default" (although idmapd is started |
| 43 |
because of "/etc/conf.d/nfs"): |
| 44 |
|
| 45 |
# ls -1 /etc/init.d/rpc* |
| 46 |
/etc/init.d/rpc.idmapd |
| 47 |
/etc/init.d/rpc.pipefs |
| 48 |
/etc/init.d/rpc.statd |
| 49 |
/etc/init.d/rpcbind |
| 50 |
|
| 51 |
# rc-update | grep rpc |
| 52 |
|
| 53 |
# rc-service nfs start |
| 54 |
* Starting rpcbind ... [ ok ] |
| 55 |
* Starting NFS statd ... [ ok ] |
| 56 |
* Setting up RPC pipefs ... [ ok ] |
| 57 |
* Starting idmapd ... [ ok ] |
| 58 |
* Mounting nfsd filesystem in /proc ... [ ok ] |
| 59 |
* Exporting NFS directories ... [ ok ] |
| 60 |
* Starting NFS mountd ... [ ok ] |
| 61 |
* Starting NFS daemon ... [ ok ] |
| 62 |
* Starting NFS smnotify ... [ ok ] |
| 63 |
|
| 64 |
# |
Archives