The patch installation instructions assume you saved the patch files in root's home directory. You may need to adjust the locations of the patch files and samba source files. If you are unfamiliar with the patch command, patch takes a patchfile containing a difference listing produced by the diff program and applies those differences to one or more original files, producing a patched version. More information can be found using the man pages. To install the patch login as root and issue the following commands.

# patch /root/samba-2.0.9/source/include/proto.h /root/proto.h.patch
# patch /root/samba-2.0.9/source/param/loadparm.c /root/loadparm.c.patch
# patch /root/samba-2.0.9/source/smbd/reply.c /root/reply.c.patch

After you have successfully patched the system files, find loadparm.o and reply.o, and remove those files manually or use make clean. By removing just the affected object files you will speed up the recompile. You may also want to change the current configuration of your makefile, options for this can be found by using configure –help. Samba comes with a rich set of options, most of which, are out of the scope of this article. I would recommend exploring these options, since many of them solve administrative problems. Next, rebuild the samba source by issuing the make command. After make has finished, you need to install the patched source, to do this issue make install. That's it, now restart samba to confirm the patch installation works properly.

Quota Configuration

The samba documentation in quota.c says it all, "This is one of the most system dependent parts of Samba, and it’s done a little differently." I have done a lot of work on system quota support. In our institution it is critical that the users quota controls the functionality of the recycle bin. I have configured our samba installation with quota support enabled, but I have found that that feature has little to do with quota control. It turns out that this option displays the capacity of a mapped Windows/Samba drive based upon the connecting user’s quota. It is a nice feature to enable so a user can see their quota usage. In terms of quota, I have removed any system dependencies associated with the patch. So it should work with a system using quotas or not, and with or without the --with-quotas support compiled into samba.

With some careful consideration, your Unix server can be integrated with samba to provide a more informative environment for your users. For example, when a user logs into a Unix server that has quotas enabled, the system does a quota check for that user. If the user were over their quota, it would be useful to suggest that their recycle bin can be deleted. Again, this allows users to manage their own data and minimizes the direct involvement of the system administrator.

Our users access their data from multiple platforms. So to completely protect the entire user data space, I wrote a wrapper for the Unix rm command to mimic the functionality of the samba recycle bin. This way when a user deletes a file from the Unix command line, the file will be moved into the same recycle bin. Another issue to consider is management of individual user recycle bins. Without proper maintenance, the recycle bins can grow quickly. Ideally, users will manage their own, but you might like to encourage timely remove of old files. The recycle bins can be scrubbed for files older than some date using the following:

find /home/*/.recycled –type f -atime +15 -exec rm {} \;

With a cron job and the find command, management of recycle bins can be automated. This will minimize the risk that a user will unexpectedly trip their quota limit. The drawback to automatically managing user data is the possibility that you remove a file that they might need. As the system administrator, you will have to judge the tradeoff on automatically managing their data.

Conclusion

With the advent of large-scale centralized storage, the feasibility of timely restores of user data is uncertain. The high-end storage market has realized this problem, and provides a mechanism to empower the users to manage their own file recovery. This patch tries to address these problems, but it still has little affect if the user overwrites a file. In this circumstance, a restore from tape will still be necessary. Future versions of this patch may provide this protection by taking a snapshot of the entire user directory. This functionality may actually replace the need for nightly backup completely.