Re: NFS and /dev/mdXpY

["J. Bruce Fields" <bfields@fieldses.org>]

On Thu, Apr 22, 2010 at 10:53:10PM +0400, Vlad Glagolev wrote:
> On Thu, 22 Apr 2010 14:25:43 -0400
> "J. Bruce Fields" <bfields@fieldses.org> wrote:
> 
> > On Sat, Apr 17, 2010 at 07:57:47PM +0400, Vlad Glagolev wrote:
> > > Well, hello there,
> > > 
> > > Posted it on linux-kernel ML also, and post it here, for more specific analysis.
> > > 
> > > I faced this problem today while trying to mount some NFS share on OpenBSD box.
> > > I mounted it successfully without any visible errors, but I wasn't able to cd there, the printed error was:
> > > 
> > > ksh: cd: /storage - Stale NFS file handle
> > > 
> > > Apropos, the partition is 5.5 TB. I tried another one on my box and it was mounted successfully. It was possible to manage files there too. Its size is ~3GB.
> > > That's why the first time I thought about some size limitations of OpenBSD/Linux/NFS.
> > > 
> > > While talking on #openbsd @ freenode, I discovered this via tcpdump on both sides:
> > > 
> > > http://pastebin.ca/1864713
> > > 
> > > Googling for 3 hours didn't help at all, some posts had similiar issue but either with no answer at all or without any full description.
> > > 
> > > Then I started to experiment with another Linux box to kill the possible different variants.
> > > 
> > > On another box I also have nfs-utils 1.1.6 and kernel 2.6.32. Mounting that big partition was unsuccessful, it got just stuck. On tcpdump I've seen this:
> > 
> > I'm a bit confused.  What kernel and nfs-utils version is running on the
> > problematic Linux server?
> 
> same. nfs-utils 1.1.6 and kernel 2.6.32.

Huh.  That should be new enough for it to be using uuid's.  I wonder why
it isn't?

--b.

> 
> > 
> > Also, what are the contents of /proc/net/rpc/nfsd.export/content and
> > /proc/net/rpc/nfsd.content after you try to access the filesystem?
> 
> # cat /proc/net/rpc/nfsd.export/content
> #path domain(flags)
> /vault	172.17.2.5(ro,insecure,root_squash,sync,wdelay,no_subtree_check)
> 
> # cat /proc/net/rpc/nfsd.fh/content 
> #domain fsidtype fsid [path]
> # 172.17.2.5 3 0x0001030500000803
> 172.17.2.5 0 0x0500030100000803 /vault
> 
> > 
> > --b.
> > 
> > > 
> > > --
> > >     172.17.2.5.884 > 172.17.2.2.2049: Flags [.], cksum 0x25e4 (correct), seq 1, ack 1, win 92, options [nop,nop,TS val 1808029984 ecr 1618999], length 0
> > >     172.17.2.5.3565791363 > 172.17.2.2.2049: 40 null
> > >     172.17.2.2.2049 > 172.17.2.5.884: Flags [.], cksum 0x25e6 (correct), seq 1, ack 45, win 46, options [nop,nop,TS val 1618999 ecr 1808029984], length 0
> > >     172.17.2.2.2049 > 172.17.2.5.3565791363: reply ok 24 null
> > >     172.17.2.5.884 > 172.17.2.2.2049: Flags [.], cksum 0x259b (correct), seq 45, ack 29, win 92, options [nop,nop,TS val 1808029985 ecr 1618999], length 0
> > >     172.17.2.5.3582568579 > 172.17.2.2.2049: 40 null
> > >     172.17.2.2.2049 > 172.17.2.5.3582568579: reply ok 24 null
> > >     172.17.2.5.3599345795 > 172.17.2.2.2049: 92 fsinfo fh Unknown/0100030005030100000800000000000000000000000000000000000000000000
> > >     172.17.2.2.2049 > 172.17.2.5.3599345795: reply ok 32 fsinfo ERROR: Stale NFS file handle POST:
> > >     172.17.2.5.3616123011 > 172.17.2.2.2049: 92 fsinfo fh Unknown/0100030005030100000800000000000000000000000000000000000000000000
> > >     172.17.2.2.2049 > 172.17.2.5.3616123011: reply ok 32 fsinfo ERROR: Stale NFS file handle POST:
> > >     172.17.2.5.884 > 172.17.2.2.2049: Flags [F.], cksum 0x2449 (correct), seq 281, ack 129, win 92, options [nop,nop,TS val 1808029986 ecr 1618999], length 0
> > >     172.17.2.2.2049 > 172.17.2.5.884: Flags [F.], cksum 0x2476 (correct), seq 129, ack 282, win 46, options [nop,nop,TS val 1618999 ecr 1808029986], length 0
> > >     172.17.2.5.884 > 172.17.2.2.2049: Flags [.], cksum 0x2448 (correct), seq 282, ack 130, win 92, options [nop,nop,TS val 1808029986 ecr 1618999], length 0
> > > --
> > > 
> > > familiar messages, eh?
> > > 
> > > Since that time I've solved that's not OpenBSD problem. So only NFS and Linux left as the reasons of this.
> > > It was possible to mount that small partition on Linux box too, the same as on OpenBSD.
> > > 
> > > But afterthat I recongnized an interesting issue: I have different sw raid setups on my storage server.
> > > I tried to mount a small partition on the same md device where 5.5TB partition is located, and got the same
> > > error message! Now I'm sure it's about NFS <-> MDADM setup, that's why I called the topic like this.
> > > 
> > > A bit about my setup:
> > > 
> > > # cat /proc/mdstat 
> > > Personalities : [linear] [raid0] [raid1] [raid6] [raid5] [raid4] [multipath] 
> > > md3 : active raid1 sdc1[0] sdd1[1]
> > >       61376 blocks [2/2] [UU]
> > >       
> > > md1 : active raid5 sdc2[2] sdd2[3] sdb2[1] sda2[0]
> > >       3153408 blocks level 5, 512k chunk, algorithm 2 [4/4] [UUUU]
> > >       
> > > md2 : active raid5 sdc3[2] sdd3[3] sdb3[1] sda3[0]
> > >       5857199616 blocks level 5, 512k chunk, algorithm 2 [4/4] [UUUU]
> > >       
> > > md0 : active raid1 sdb1[1] sda1[0]
> > >       61376 blocks [2/2] [UU]
> > >       
> > > unused devices: <none>
> > > 
> > > md0, md1, and md3 aren't so interesting, since fs is created directly on them, and that's a _problem device_:
> > > 
> > > # parted /dev/md2
> > > GNU Parted 2.2
> > > Using /dev/md2
> > > Welcome to GNU Parted! Type 'help' to view a list of commands.
> > > (parted) p free                                                           
> > > p free
> > > Model: Unknown (unknown)
> > > Disk /dev/md2: 5998GB
> > > Sector size (logical/physical): 512B/512B
> > > Partition Table: gpt
> > > 
> > > Number  Start   End     Size    File system     Name   Flags
> > >         17.4kB  1049kB  1031kB  Free Space
> > >  1      1049kB  2147MB  2146MB  linux-swap(v1)  swap
> > >  2      2147MB  23.6GB  21.5GB  xfs             home
> > >  3      23.6GB  24.7GB  1074MB  xfs             temp
> > >  4      24.7GB  35.4GB  10.7GB  xfs             user
> > >  5      35.4GB  51.5GB  16.1GB  xfs             var
> > >  6      51.5GB  5998GB  5946GB  xfs             vault
> > >         5998GB  5998GB  507kB   Free Space
> > > 
> > > # ls /dev/md?*
> > > /dev/md0  /dev/md1  /dev/md2  /dev/md2p1  /dev/md2p2  /dev/md2p3  /dev/md2p4  /dev/md2p5  /dev/md2p6  /dev/md3
> > > 
> > > It's very handy partitioning scheme where I can extend (grow 5th raid) with more hdds only /vault partition while "loosing" (a.k.a. not using for this partition) only ~1gb of space from every 2TB drive.
> > > 
> > > System boots ok and xfs_check passes with no problems, etc.
> > > The only problem: it's not possible to use NFS shares on any partition of /dev/md2 device.
> > > 
> > > Finally, my question to NFS and MDADM developers: any idea?
> > > 
> > > -- 
> > > Dont wait to die to find paradise...
> > > --
> > > Cheerz,
> > > Vlad "Stealth" Glagolev
> > 
> > 
> 
> 
> -- 
> Dont wait to die to find paradise...
> --
> Cheerz,
> Vlad "Stealth" Glagolev