Ubuntu – Can create and delete files through samba, but not modify

There is, probably, a sharing/locking problem on your files. The background process is temparing the files while they are still written to by whoever is creating them.

remove the:

locking = no

from your smb.conf file. It should solve the problem. This parameter should be used only on read only shares. Like cd. Make sure that all acess to those files is through samba share. If you access them directly from the os or from nfs share. Then read this carefully.

MMM i few things i would recommend to you:

• look for signs of strange processes, with chkrootkit ( http://www.chkrootkit.org )

• Do a portscan with nmap from a different machine to make sure nothing strage is open or that you have anything else secure.

• Check your firewall rules and do changes if you see it is too wide to outsiders

• Verify your samba conf and limit it by the known ips you have if you don't share the data with anyone else, this will keep any outsiders from using it.

• Not sure if this would be a problem to you but you can aswell set samba to use passwords to access/create the data, that is ofc assuming the files are being created by a 3rd party and not within your own system, but then checking if your system has been rootkited as pointed above would be the best.