OS/400 File Systems


What file systems does Web Server/400 support? Below is a list of the supported file systems and a short description of the strengths of each.

QSYS
Most of the existing AS/400 applications deal with data stored in QSYS. All DB2/400 databases and OS/400 programs exist here.

QDLS
Many installations are currently setup to have PCs attach to their AS/400 through the DOS Extended and OS/2 1.x versions of Client Access/400. These clients are usually setup to access shared folders. This allows for easy access to stream files on the host that can be served by Web Server/400. It is also much easier to store typical Web multimedia content in QDLS than in QSYS.

Root
Being the newest file system, this is the most efficient and flexible file system for accessing stream files. New products, such as the new WIN16 and OS/2 Optimized clients of Client Access/400, are supporting the Root file system. The names of files and depth of directories have no practical limit. The speed of this file system makes it ideal for serving and creating large Web documents.

IFS currently has two specialized file systems under it called QOpenSys and QLANSrv. QOpenSys only has one distinction between it and the rest of the root file system: files and directories are case sensitive. A file named HEADER.HTML is different from a file named header.html. This is the way a standard Unix file system works. If you are transferring a Web site from a Unix machine to Web Server/400 and the Unix Web site depended on the case of file names and directories, moving the files into QOpenSys and setting up your Document Root to point to a directory under the QOpenSys file system would support this seamlessly.

The QLANSrv file system has some advantages and disadvantages for being used with Web Server/400. One advantage is the workstations attached to the AS/400 with an FSIOP and the LAN Server/400 product can easily and quickly access the content on the Web site. However, there are two disadvantages as well.

  1. Accessing files in QLANSrv from the AS/400 is actually relatively slow. This file system's speed advantages are only obtainable from workstations.
  2. Normal AS/400 security is not implemented in the QLANSrv file system. LAN Server/400 is responsible for the security and it implements a different security model than that of the AS/400.
It should also be noted that QLANSrv is not accessible unless you have the LAN Server/400 product installed.