Originally posted by: ThatSeattleGuy

I'm administering a client's VERY old AIX 4.3.3 system. I'm trying to NFS mount a directory (/transfer) on the AIX system from a modern (RHEL 5.5) Linux client. I'm able to make the mount happen fine, and I've deliberately (for testing) made everything as loose as possible:

# more /etc/exports
+/transfer -rw=*,access=*,root=*

# exportfs -va
exportfs: 1831-187 re-exported /transfer

# showmount -e
export list for aix:
/transfer *

But while the Linux client can mount this fine, and read it, it only sees it as read-only, no matter what I do:

root@linux ~# cat /etc/fstab
aix:/transfer /mnt/aixxfer nfs defaults,noacl 0 0

root@linux ~# mount /mnt/borisxfer

root@linux ~# mount
aix:/transfer on /mnt/aixxfer type nfs (rw,noacl,addr=192.168.1.2)

root@linux ~# ls -la /mnt/borisxfer/
total 460
drwxrwsrwx 10 root sys 512 Sep 23 14:29 .
drwxr-xr-x 3 root root 4096 Sep 23 14:36 ..
drwxr-sr-x 11 root root 512 Nov 3 2009 bci
drwxrwx--- 2 root root 512 Jun 25 2009 lost+found

root@linux ~# touch /mnt/borisxfer/xyzzy
touch: cannot touch `/mnt/borisxfer/xyzzy': Read-only file system
I've banged on this for a few hours trying MANY different options on both sides, and using any number of different userids on the linux side (root, a common user with the same UID, an anonymous user). No joy.

What am I doing wrong and/or how can I trace what's going wrong here?

Many thanks.
TSG
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Originally posted by: ThatSeattleGuy

Sorry, some creative edits went awry. Here's a better version of the question:

I'm administering a client's VERY old AIX 4.3.3 system. I'm trying to NFS mount a directory (/transfer) on the AIX system from a modern (RHEL 5.5) Linux client. I'm able to make the mount happen fine, and I've deliberately (for testing) made everything as loose as possible:

1. more /etc/exports

/transfer -rw=*,access=*,root=*

1. exportfs -va

exportfs: 1831-187 re-exported /transfer

1. showmount -e

export list for aix:
/transfer *

But while the Linux client can mount this fine, and read it, it only sees it as read-only, no matter what I do:

root@linux ~# cat /etc/fstab
aix:/transfer /mnt/aixxfer nfs defaults,noacl 0 0

root@linux ~# mount /mnt/aixxfer

root@linux ~# mount
aix:/transfer on /mnt/aixxfer type nfs (rw,noacl,addr=192.168.1.2)

root@linux ~# ls -la /mnt/aixxfer/
total 460
drwxrwsrwx 10 root sys 512 Sep 23 14:29 .
drwxr-xr-x 3 root root 4096 Sep 23 14:36 ..
drwxr-sr-x 11 root root 512 Nov 3 2009 bci
drwxrwx--- 2 root root 512 Jun 25 2009 lost+found

root@linux ~# touch /mnt/aixxfer/xyzzy
touch: cannot touch `/mnt/aixxfer/xyzzy': Read-only file system
I've banged on this for a few hours trying MANY different options on both sides, and using any number of different userids on the linux side (root, a common user with the same UID, an anonymous user). No joy.

What am I doing wrong and/or how can I trace what's going wrong here?

Many thanks.
TSG
#AIX-Forum

Originally posted by: john1212

do:

root@aix~# ln -s /transfer /tmp/transfer_nfs
ls -l / |grep transfer
ls -l /tmp | grep transfer_nfs

more /etc/exports
/tmp/transfer_nfs -rw=*,access=*,root=*

root@linux ~# cat /etc/fstab
aix:/transfer_nfs /mnt/aixxfer nfs defaults,noacl 0 0

root@linux ~# mount /mnt/borisxfer

root@linux ~# mount
aix:/transfer on /mnt/aixxfer type nfs (rw,noacl,addr=192.168.1.2)

root@linux ~# ls -la /mnt/borisxfer/

........
touch /mnt/borisxfer/xyzzy
#AIX-Forum

Originally posted by: ThatSeattleGuy

All good thoughts - many thanks. But no better result:

root@aix ls -l /tmp | grep nfs
lrwxrwxrwx 1 root system 9 Sep 26 11:07 xfer_nfs -> /transfer

root @aix ls -l / | grep transfer
drwxrwsrwx 11 root sys 512 Sep 24 22:19 transfer

root@aix exportfs -va
Exported /tmp/xfer_nfs

root@aix exportfs
/tmp/xfer_nfs -rw=*,access=*,root=*

root@aix more /etc/exports | grep nfs
/tmp/xfer_nfs -rw=*,access=*,root=*
now on linux side

[root@linux$ cat /etc/fstab | grep nfs
aix:/tmp/xfer_nfs /mnt/aixxfer nfs defaults,rw,noacl 0 0

root@linux mount /mnt/aixxfer/
root@linux

rooot@linux$ mount | grep nfs
aix:/tmp/xfer_nfs on /mnt/aixxfer type nfs (rw,noacl,addr=192.168.1.2)

root@linux$ cd /mnt/aixxfer
root@linux aixxfer$ touch xyz
touch: cannot touch `xyz': Read-only file system
#AIX-Forum

Originally posted by: ThatSeattleGuy

One more crucial datum - and I feel pretty stupid for not having tried this earlier, so apologies in advance:

If I mount the exported filesystem LOCALLY on the AIX side - no linux involved - it's STILL read-only. So we can focus on AIX and ignore Linux for now.

Question: The user created this directory with the SUID bit set in the group permissions - not sure why - but is it possible NFS is locking down on it because of that?

1. ls -lad /transfer

drwxrwsrwx 11 root sys 512 Sep 24 22:19 /transfer
#
#AIX-Forum

Originally posted by: ThatSeattleGuy

( of course, I meant "SGID bit set", not suid bit...)
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Originally posted by: SystemAdmin

well, you're just 1 command away from a real-world test, I'd go for it.

in general with nfs, I like to look at the network packets. wireshark does a fine job about decoding nfs/rpc and the protocols are pretty much assisting with reasonable error codes.
#AIX-Forum

Originally posted by: ThatSeattleGuy

well, you're just 1 command away from a real-world test, I'd go for it.

??? Not sure what's being implied - go for what? I did test it already using a same-system (localhost) mount, and it's still read-only.

I'll look to see if there's a wireshark package available for AIX 4.3.3. Lots of stuff isn't so accessible for an 11-year-old OS version. :)

thanks /tsg/
#AIX-Forum

Originally posted by: SystemAdmin

excuse my imprecision, i meant: test removing the SGID bit.

i doubt there is a wireshark for aix 4.3 but you can capture with iptrace or tcpdump and analyze on windows or linux.

regards
Delgado
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Originally posted by: ThatSeattleGuy

delgado: thanks, sorry for not understanding. I did remove the SGID bit and re-exported and the result was the same - the mount was read-only whether on the Linux box or the localhost loopback mount on the same AIX box.

thanks much
#AIX-Forum

Originally posted by: john1212

No comment.
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