How to increase the maximum [rw]size NFS server supports from 8k to 32k? First verify the maximum [rw]size of NFS server by checking the NFSSVC_MAXBLKSIZE, found in the Linux kernel source file ./include/linux/nfsd/const.h. If it is defined as "#define NFSSVC_MAXBLKSIZE (8*1024)", change that to #define NFSSVC_MAXBLKSIZE (32*1024) and recompile the kernel. [root@raj nfsd]# grep NFSSVC_MAXBLKSIZE const.h #define NFSSVC_MAXBLKSIZE (8*1024) [root@raj nfsd]# After compiling and booting with the new kernel check NFS server supports 32k block size by mounting an export point: [root@raj nfsd]# mount -o rsize=32768,wsize=32768 127.0.0.1:/home /mnt/win1 [root@raj nfsd]# cat /proc/2868/mounts rootfs / rootfs rw 0 0 /dev/root / ext3 rw 0 0 /proc /proc proc rw 0 0 usbdevfs /proc/bus/usb usbdevfs rw 0 0 none /dev/pts devpts rw 0 0 /dev/hda7 /home ext3 rw 0 0 none /dev/shm tmpfs rw 0 0 127.0.0.1:/home /mnt/win1 nfs rw,v3,rsize=32768,wsize=32768,hard,udp,lock,addr=127.0.0.1 0 0 2868- pid of nfsd. Use the following command to find pid of nfsd. ps-aux | grep nfsd If the server doesn't suppor 32k block size, mount command with [rw]size 32k will simply succeeds. NFS client uses the max size supported by NFS server. Easy wa to verify it is using the /proc file system as shown above. On Wed, 05 Jan 2005 Raj Kumar wrote : >Thanks Vindoh for replying to my question! > >I will add the options to /etc/fstab as you mentioned. But is const.h the only file I should change to make the NFS server support 32K size? Is there an easy way to verify if the NFS server is indeed serving NFS clients with 32K? Should I also modify const.h on all NFS client machines also? I'm using RHEL3 and the kernel version is 2.4.21-27.0.1.ELsmp. It looks like this patchset didn't make it into kernel version until 2.4.27-xx or so. Is it true? > >Thanks again! >Raj > >On Wed, 05 Jan 2005 Vinodh Cuppu wrote : > >On 01/04/2005 10:38 PM, Raj Kumar wrote: > > > >>What changes have to be made to enable 32K rsize/wsize for both NFS Server and Client? > >> > >>with only this change made > >>to the file /usr/src/linux-2.4/include/linux/nfsd/const.h: > >> > >>NFSSVC_MAXBLKSIZE = 32*1024 (instead of 8*1024) > >> > >>and compiling kernel suffice? > >> > >>Does both NFS server and client support 32k rsize/wsize or only NFS client? > >> > >Add "rsize=32768,wsize=32786" to the options portion of the mount in /etc/fstab, like the following > > > >machine:/export_dir /nfs_mount nfs other_options,rsize=32768,wsize=32786 0 0 > > > >_______________________________________________ > >rhn-users mailing list > >rhn-users@redhat.com > >https://www.redhat.com/mailman/listinfo/rhn-users >_______________________________________________ >rhn-users mailing list >rhn-users@redhat.com >https://www.redhat.com/mailman/listinfo/rhn-users <A target="_blank" HREF="http://clients.rediff.com/signature/track_sig.asp"><IMG SRC="http://ads.rediff.com/RealMedia/ads/adstream_nx.cgi/www.rediffmail.com/inbox.htm@Bottom" BORDER=0 VSPACE=0 HSPACE=0></a>