[openafs.git] / doc / txt / winnotes / afs-install-notes.txt

OpenAFS for Windows 1.3.72 Installation Notes
---------------------------------------------

The OpenAFS for Windows product was very poorly maintained throughout the 
1.2.x release cycle.  While the Unix version was being enhanced and its 
quality was improving the Windows version stagnated.  The IBM AFS 3.6 product 
was not designed for the Windows 2000/XP/2003 operating system nor was it 
architected with highly disconnected environments in mind.

The 1.3.x series of releases not only fixes a large number of bugs in the 1.2 
series but also attempts to enhance the functionality of the product to better 
fit the usage model of today's users.  Several items standout.  


1. The Kerberos 4 infrastructure on which the 1.2 series is reliant is no 
longer secure.  Cross-realm Kerberos is very important in the AFS context and 
most sites have or are migrating to Kerberos 5 environments.  The 1.3 series 
integrates with the MIT Kerberos for Windows 2.6.x product to provide Kerberos 
5 functionality including the ability to auto-renew credentials and obtain 
single sign-on capabilities with the Microsoft Windows Kerberos Logon Service.

As of 1.3.65, the OpenAFS client will directly use Kerberos 5 tickets as tokens if 
KFW is installed.  The client requires that all of the AFS Servers with which it 
communicates support the use of Kerberos 5 tickets as tokens (aka 2b tokens).
This means that all of the AFS servers must be running OpenAFS release 1.2.8 or 
higher.  Transarc servers do not support Kerberos 5 tickets as tokens.

When using a Microsoft Windows Active Directory as the KDC which issues the 
service ticket for the AFS cell there are two things to consider.  First, the 
Kerberos 5 tickets issued by Active Directory can be quite large when compared 
to tickets issued by a traditional KDC due to the incorporation of 
authorization data in the PAC.  If this is your situation you either must 
modify your 1.2.x servers to support tokens larger than a few hundred bytes; 
or install the 1.3.64 or higher release on your servers.  Second, Windows 2003 
Active Directory will issue service tickets utilizing the DES-CBC-MD5 enctype. 
OpenAFS releases older than 1.3.64 will not properly support this enctype.


2. The AFS Client Service does not provide robust behavior in an environment 
with a plug-n-play network environment.  Changes to the number of network 
adapters or the assigned IP addresses will cause the service to panic.  The 
recommended work around for this problem is to install the Microsoft Loopback 
Adapter on the machine.  When the MLA is installed with a static IP address 
the AFS Client Service will bind only to the loopback and not be affected by 
changes to state of other network adapters installed on the system.  

Starting in the 1.3.65 release the installers provided by OpenAFS.org will 
install the Microsoft Loopback Adapter for you with a name of "AFS" and a 
pre-assigned IP address in the 10.x.x.x range.

One of the benefits of using the MLA is that the NETBIOS names used for the 
AFS Client's SMB server do not have to be published on any adapter other than 
the MLA.  This means that the names no longer need to be unique.  When the MLA 
is in use, the NETBIOS name associated with the AFS Client Service is simply 
"AFS".  When the MLA is not in use the NETBIOS name is "MACHINE-AFS".

When the MLA is installed, UNC paths of the form \\AFS\cellname\path may be used.


3. Traditionally, when the AFS Client Service starts it must be able to 
access the "root.afs" volume of the default cell.  The "root.afs" volume
contains a set of read-only and read-write mount points to the "root.cell"
volumes of various cells the administrator of the default cell believes
should be accessible.  If the "root.afs" volume is 
inaccessible when the client service is started, the service will panic.  
Since many users now use laptops or otherwise operate in disconnected 
environments in which a VPN may be needed to access the cell's servers, it is 
often the case that the "root.afs" volume for the default cell is not 
reachable and the AFS Client Service will not successfully start. 
 
The OpenAFS Client Service now supports a fake "root.afs" volume which is 
dynamically constructed when the service starts.  This mode is called 
Freelance mode.  Freelance mode is turned on by default.

The contents of the
fake "root.afs" volume are constructed dynamically as cells are accessed.
When the fake "root.afs" volume is constructed it will only contain two
mount points: a read-only and read-write mount point used to access the
"root.cell" volume of the default AFS cell.  Any attempt to access a 
valid cell name will automatically result in a new mount point 
being created in the fake "root.afs" volume.  If the cellname begins with
a "." the mount point will be read-write; otherwise the mount point will
be read-only.  These mount points are preserved in the registry at key:
  HKLM\SOFTWARE\OpenAFS\Client\Freelance

Additional mount points may be manually created using the "fs mkmount"
command.  Mount points may be removed using the "fs rmmount" command.

    fs mkmount \\AFS\all\athena.mit.edu root.cell athena.mit.edu
    fs mkmount \\AFS\all\.athena.mit.edu root.cell athena.mit.edu -rw
    fs rmmount \\AFS\all\athena.mit.edu
    fs rmmount \\AFS\all\.athena.mit.edu
     

4. The OpenAFS for Windows client will use AFSDB DNS records to 
discover cell information when it is not located in the local CellServDB file 
(\Program Files\OpenAFS\Client\CellServDB).


5. OpenAFS for Windows 1.3.72 only supports Windows 2000, Windows XP, and 
Windows 2003.  Windows NT 4.0 and the entire Windows 9x/Me line are no
longer supported.  Older releases of OpenAFS are available for download
if those operating systems must be supported.  The last version with support
for Win9x is 1.2.2b.  The last version with support for Windows NT 4.0 is
1.2.10.


6. OpenAFS for Windows installs a WinLogon Network Provider to provide
Integrated Logon (Single Sign-on) functionality. Integrated Logon can be used 
when the Windows username and password match the username and password 
associated with the default cell's Kerberos realm.  For example, if the 
windows username is "jaltman" and the default cell is "athena.mit.edu", then 
Integrated Logon can be successfully used if the windows password matches the 
password used for the Kerberos principal "jaltman@ATHENA.MIT.EDU".

Integrated Logon is required if you desire the ability to store roaming user 
profiles within the AFS file system.  OpenAFS does not provide tools for 
synchronizing the Windows and Kerberos user accounts and passwords.

If KFW is installed, the Integrated Logon will use Kerberos 5 to obtain 
tokens.  Otherwise, Kerberos 4 is used.

There is a High Security mode for use with Integrated Logon when multiple 
users will share a single machine.  There are known problems with this mode.  
In particular, if you are using this mode it is crucial that new AFS tokens 
not be obtained after the logon session starts except via the AFS Systray tool 
as started by the AFS Network Provider.  If the AFS Systray tool is stopped 
you must log off to obtain new tokens.  Do not use external tools such as 
"aklog.exe" if High Security mode is turned on. As of 1.3.70, OpenAFS supports 
Authenticated SMB connections which removes the need for High Security mode. 
DO NOT USE IT!!!!! 

What Integrated Logon does not do:
 (a) Integrated Logon does not have the ability to obtain Kerberos 5
     tickets for use during the Windows Session.  At the current time there
     is no mechanism by which a Kerberos 5 CCAPI credentials cache can
     be constructed during the logon process such that it will exist in 
     the user's logon session.
 (b) Integrated Logon does not have the ability to cache the user's 
     username and password for the purpose of obtaining tokens if the
     Kerberos KDC is inaccessible at logon time.


7. The AFS Systray tool (afscreds.exe) supports several new command line 
options: 

    -A = autoinit 
    -M = renew drive maps 
    -N = ip address change detection 
    -Z = unmap drives

autoinit will result in automated attempts to acquire AFS tokens when 
afscreds.exe is started.  afscreds.exe will attempt to utilize tickets stored
in the MSLSA credentials cache; any existing CCAPI credentials cache; and
finally display an Obtain Tokens dialog to the user.  When used in combination 
with ip address change detection, afscreds.exe will attempt to acquire AFS 
tokens whenever the IP address list changes and the Kerberos KDC is 
accessible.

The renew drive maps option is used to ensure that the user drive maps 
constructed via the AFS tools (not NET USE) are re-constructed each time
afscreds.exe is started.

By default afscreds.exe is configured by the OpenAFS.org installers to use -A 
-N -M -Q as startup options.  Currently, there is no UI to change this selection 
after install time although these options may be altered via the registry either 
per machine or per user.  See AfscredsShortcutParams in registry.txt.


8. As of 1.3.71, the OpenAFS for Windows client supports a local Windows
authorization group called "AFS Client Admins".  This group is used in
place of the "Administrators" group to determine which users are allowed
to modify the AFS Client Service configuration via either afs_config.exe
or fs.exe.  For example, the following fs.exe commands are now restricted 
to members of the "AFS Client Admin" group:

    - checkservers with a non-zero timer value
    - setcachesize
    - newcell
    - sysname with a new sysname list
    - exportafs
    - setcell
    - setserverprefs
    - storebehind
    - setcrypt
    - cscpolicy
    - trace

Setting the default sysname for a machine should be done via the registry and 
not via "fs sysname".

The local "SYSTEM" account is always a member of the "AFS Client Admin" group.

The initial membership of the "AFS Client Admin" group when created by the 
installer is equivalent to the local "Administrators" group.


9. The AFS Client should support UNC paths everywhere.  Power users that make
extensive use of the command line shell, cmd.exe, might want to consider using 
JP Software's 4NT command processor.  Unlike cmd.exe, 4NT does fully support
UNC paths and can use a UNC path as the default device.


10. The AFS Client ships with its own version of aklog.exe which should be 
used in preference to those obtained by third party sources.  The OpenAFS
aklog.exe supports Kerberos 5 as well as the ability to auto-generate
pts IDs for user's obtaining tokens to foreign cells.

Usage: aklog [-d] [[-cell | -c] cell [-k krb_realm]]
             [[-p | -path] pathname]
             [-noprdb] [-force]
             [-5 | -4]

   -d gives debugging information.
   krb_realm is the kerberos realm of a cell.
   pathname is the name of a directory to which you wish to authenticate.
   -noprdb means don't try to determine AFS ID.
   -5 or -4 selects whether to use Kerberos V or Kerberos IV.
      (default is Kerberos V)
   No commandline arguments means authenticate to the local cell.


11. The AFS Server functionality provided with OpenAFS 1.3.72 might work but 
should be considered highly experimental.  It has not been thoroughly tested.
Any data which would cause pain if lost should not be stored in an OpenAFS 
Server on Windows.

A few notes on the usage of the AFS Client Service if it is going to be 
used with the OpenAFS AFS Server:

(a) When the AFS Server is installed Freelance mode must be turned off.  

(b) The AFS Server and related tools only support the built in kaserver
(Kerberos IV).  If the AFS Server is being used, MIT Kerberos for Windows
should not be used.


12. The OpenAFS for Windows installers now include Symbol information which 
should be installed if you are experiencing problems and need to send crash 
reports.  This is true in both the release and the debug versions of the 
installers.  The differences between the release and debug versions are 
whether or not the binaries were compiled with optimization; whether the
debug symbols are installed by default; and whether additional debug 
statements were compiled into the binaries.


13. OpenAFS for Windows does not support files larger than 2GB.  


14. Local RPC is used as the default RPC mechanism for setting 
tokens.  TCP RPC is required to be installed and is used for debugging 
and other functions.


15. OpenAFS for Windows automatically open ports in the Windows 
Internet Connection Firewall.


16. The OpenAFS for Windows installer by default activates a weak form of 
encrypted data transfer between the AFS client and the AFS servers.  This
is often referred to as "fcrypt" mode.


17. OpenAFS 1.3.71 adds support for authenticated SMB connections using 
either NTLM or GSS SPNEGO (NTLM, Kerberos 5, ...).  In previous versions
of OpenAFS the SMB connections were unauthenticated which left open the
door for several security holes which could be used to obtain access to
the use of other user's tokens on shared machines.  With the introduction
of authenticated SMB connections the so called High Security mode should
no longer be used.  

When GSS SPNEGO results in a Kerberos 5 authentication, the Windows SMB
client will attempt to retrieve service tickets for "cifs/afs@REALM" (if 
the loopback adapter is in use) or "cifs/machine-afs@REALM" (if the loopback
adapter is not being used).  It is extremely important that this service 
principal not exist in the KDC database.   If the request for this ticket
fails, a subsequent request for "cifs/HOST$@REALM" will be issued.  This 
service principal should exist in the KDC database.  The key associated 
with this service principal must match the key assigned to 
"host/machine@REALM".  If the local machine is part of a Windows Domain
this will all be taken care of for you.  If the local machine is using
a non-MS KDC for authentication, then your KDC administrator will have to
add these service principals to the list of principals to be maintained
for each host.


18. As of 1.3.70, INI files are no longer used for the storage of AFS 
configuration data.  No longer are there any AFS related files stored in the
%WINDIR% directory.  The CellServDB file is no longer called "afsdsbmt.ini"
and it is stored in the OpenAFS\Client directory.  The afs_freelance.ini
and afsdsbmt.ini file data has been moved to the registry.  

IMPORTANT: while the CellServDB file location and freelance mountpoint
data will be automatically migrated; there is no mechanism for automatic
migration of Submounts, Drive Mappings, Active Maps, and CSCPolicy data.


19. As of 1.3.70, the OpenAFS Client is compatible with Windows XP SP2
and Windows 2003 SP1.  The Internet Connection Firewall will be 
automatically adjusted to allow the receipt of incoming callback messages 
from the AFS file server.  In addition, the appropriate Back Connection 
entries are added to the registry to allow SMB authentication to be 
performed across the loopback connection.


20. As of 1.3.70, the OpenAFS Client Service supports the CIFS Remote
Admin Protocol which provides browsing of server and share information.
This significantly enhances the interoperability of AFS volumes within the
Explorer Shell and Microsoft Office applications.


21. OpenAFS will now automatically forget a user's tokens upon Logoff
unless the user's profile was loaded from an AFS volume.  In this situation
there is no mechanism to determine when the profile has been successfully
written back to the network.  It is therefore unsafe to release the user's
tokens.  Whether or not the profile has been loaded from the registry can
be determined for Local Accounts, Active Directory accounts and NT4 
accounts.
                                                   

22. Terminal Server installations.
When installing under Terminal Server, you must execute the NSIS installer
(.exe) from within the Add/Remove Programs Control Panel.  Failure to do so 
will result in AFS not running properly.  The AFS Server should not 
be installed on a machine with Terminal Server installed.


23. AFS is a Unix native file system.  As such the OpenAFS client attempts
to treat the files stored in AFS as they would be on Unix.  File and directory
names beginning with a "." are automatically given the Hidden attribute so
they will not normally be displayed.


24. Some organizations which have AFS cell names and Kerberos realm names
which differ by more then just lower and upper case rely on a modification
to krb524d which maps a Kerberos 5 ticket from realm FOO to a Kerberos 4
ticket in realm BAR.  This allows user@FOO to appear to be user@bar for
the purposes of accessing the AFS cell.  As of OpenAFS 1.2.8, support was
added to allow the immediate use of Kerberos 5 tickets as AFS (2b) tokens.
This is the first building block necessary to break away from the 
limitations of Kerberos 4 with AFS.  By using Kerberos 5 directly we
avoid the security holes inherent in Kerberos 4 cross-realm.  We also
gain access to cryptographically stronger algorithms for authentication
and encryption. 

Another reason for using Kerberos 5 directly is because the krb524 service
runs on a port (4444) which has become increasingly blocked by ISPs.  The
port was used to spread a worm which attacked Microsoft Windows in the 
summer of 2003.  When the port is blocked users find that they are unable
to authenticate.

Replacing the Kerberos 4 ticket with a Kerberos 5 ticket is a win in all
situations except when the cell name does not match the realm name and
the principal names placed into the ACLs are not the principal names from
the Kerberos 5 ticket.  To support this transition, OpenAFS for Windows
in 1.3.72 adds a new registry value to force the use of krb524d.  However,
the availability of this option should only be used by individuals until
such time as their organizations can provide a more permanent solution.


25. The Status Cache (AFS Config Control Panel: Advanced Page) is defined
to have a maximum number of entries.  Each entry represents a single file
or directory entry accessed within the AFS file system.  When the maximum
number of entries are allocated, entries will begin to be reused according
to a least recently used (LRU) algorithm.  If the number of files or 
directories being accessed repeatedly by your applications is greater then
the maximum number of entries, your host will begin to experience thrashing
of the Status Cache and all requests will result in network operations.

If you are experiencing poor performance you might want to increase the 
maximum number of Status Cache entries.  Each entry requires 164K.  Only
those entries which are used are allocated.


------------------------------------------------------------------------

Reporting Bugs:

Bug reports should be sent to openafs-bugs@openafs.org.  Please include as 
much information as possible about the issue.  If you are reporting a crash, 
please install the debugging symbols by re-running the installer.  If a dump 
file is available for the problem include it along with the AFS Client Trace 
file  %WINDIR%\TEMP\afsd.log.  The AFS Client startup log is 
%WINDIR%\TEMP\afsd_init.log.  Send the last continuous block of log 
information from this file.

------------------------------------------------------------------------

How to Contribute to the Development of OpenAFS for Windows:

Contributions to the development of OpenAFS for Windows are needed. 
Contributions may take many forms including cash donations, support contracts, 
donated developer time, and even donated tech writer time.

If you wish to be involved in OpenAFS for Windows development please join the 
openafs-win32-devel@openafs.org mailing list.

  https://lists.openafs.org/mailman/listinfo/openafs-win32-devel

User questions should be sent to the openafs-info@openafs.org mailing list.  

  https://lists.openafs.org/mailman/listinfo/openafs-info

You must join mailing lists if you wish to post to the list without incurring 
a moderation delay.