NFS issues: "File size limit exceeded"

edenCC · 03-04-2008, 12:17 AM

Hi, list;
I'm using RH9, with a modified kernel 2.4.26.

when I mount a NFS partition locally, and copy some big files(larger then 2giga bytes) to it, I got an error message: "File size limit exceeded".

I searched around, and found some tips there:
1, NFS in TCP mode has good performance, while running in UDP mode very poor.
2, NFS v2 supports UDP only, while NFS v3 set TCP mode as its default.
3, NFS v2 may have "file size limit exceeded" issue.

When I'm coping files to the RH9, I got good performance, about 30MB/S, but faced the issue mentioned above.
I guess if I update NFS service from v2 to v3, the "file size limit exceeded" should be fixed. But indeed the v2 NFS supports TCP:

Code:

rh9# /usr/sbin/rpcinfo -p localhost
   program vers proto   port
    100000    2   tcp    111  portmapper
    100000    2   udp    111  portmapper
    100011    1   udp    665  rquotad
    100011    2   udp    665  rquotad
    100011    1   tcp    668  rquotad
    100011    2   tcp    668  rquotad
    100003    2   udp   2049  nfs
    100021    1   udp  32781  nlockmgr
    100021    3   udp  32781  nlockmgr
    100005    1   udp    682  mountd
    100005    1   tcp    685  mountd
    100005    2   udp    682  mountd
    100005    2   tcp    685  mountd

Did I get some wrong, and How can I fix the size exceeded issue please?

jschiwal · 03-04-2008, 01:16 AM

Wouldn't it be easier to upgrade to a less ancient edition of RH or Fedora Core?
Most distro's support NFS v4 now. Also look into the filesystem used and the version.
Some filesystems may have a 2 or 4 GB filesize limit with older versions of the filesystem.

edenCC · 03-04-2008, 02:05 AM

thanks for the reply
But we have many servers, and the good ones are mostly for online services.
Currently, it works fine on an RHEL AS3, with good performance.

jschiwal · 03-04-2008, 04:11 AM

Do use a user-level nfs server or the nfs-kernel-server? You may need to upgrade the kernel to retain the speeds you are getting, and build the cooresponding user-land tools. I still think an upgrade from RH9 would be a better idea. It could take care of upgrading nfs and you wouldn't have to worry as much about security vulnerabilities that you can't patch anymore using an unsupported and outdated version.