GroupWise is a hierarchical, single-instance store,
store-and-forward e-mail system. "Hierarchical" means that the directory
structure is based on a hierarchy of masters and slaves. "Single-instance
store" means that GroupWise uses a database technology which creates only a
single instance of a message to multiple users on a post office. Finally,
"store-and-forward" means that GroupWise delivers messages through the system
by moving the mail from one file folder to another until it reaches its final
destination.
GroupWise Domain Architecture
Domain Hierarchy
GroupWise organizes post offices into domains, and domains into a system.
Directory replication between all servers and all domains is automatic, but
cannot occur between systems without special configuration. One domain in the
system is designated as the "primary" domain, which makes it the "master"
within the system with full privileges to administer all objects in any domain.
All other domains are called "secondary" domains. Secondary domain
administrators have privileges to manage objects within their domain only. All
system administration is done from the domain; none of it is done from the post
office.
Directory Structure and Replication
In GroupWise 5.x, the directory is integrated with Novell Directory Services
(NDS), though not fully so. NDS is the master directory, and all changes must
be made through NDS. However, GroupWise maintains its own directory separate
and distinct from NDS. Changes are made to the GroupWise 5.x system using
NetWare Administrator (NWAdmin or NWAdmn32) and a GroupWise administration
snap-in module that gets added during the installation of GroupWise 5.x.
NOTE: NetWare Administrator is much like Microsoft Management Console
(MMC) in that it is a single location for administering the entire NetWare
system. Like MMC, NetWare Administrator is extensible, allowing third parties
to integrate snap-in dynamic-link libraries (DLLs) that add functionality to
NetWare Administrator.
Objects in a GroupWise System These include:
- Users: Native GroupWise recipients (mailboxes). In GroupWise 5.x, users
are NetWare users with associated GroupWise accounts. All administration of
users is done through separate pages in the properties of a NetWare user
object.
- External entities: Similar in concept to "custom recipients" in
Exchange.
- Resources: A resource is a unique mailbox that represents either a place
(for example, a conference room), or a resource (for example, an overhead
projector). Each resource has an owner that has full proxy permissions to the
resource mailbox.
- Distribution Lists: Groups of users, for easy addressing.
- Libraries: A document store in a GroupWise post office. GroupWise has
built-in document management functionality, and the library is where all
documents are stored for easy search and retrieval. The Microsoft equivalent is
Microsoft SharePoint Portal Server 2001.
- Post Offices: The central store for messages, documents, and client
communication. Users connect to post offices. They do not connect to
domains.
- Domains: At one level, the domain is the central focus for administration
of the directory and for message delivery both within and outside of the
domain. Administrators connect to domains. They do not connect to post offices.
At a higher level, a domain is merely a logical collection of post offices,
similar in concept to the Exchange site.
- Agents: The entities responsible for server-side functions,
specifically, the message transfer agent (MTA), the post office agent (POA),
and the administration agent (ADA). The MTA and ADA are domain objects. The POA
is a post office object. In GroupWise 5.5, all ADA functions are combined into
the MTA and POA so that the ADA is completely eliminated.
- Gateways: Connectors to both native and foreign systems. GroupWise has
many gateways which run on many platforms, some of which are: Async, X.25,
X.400, SMTP (called the GroupWise Internet Access agent, or GWIA, in GroupWise
5.x), Web Access, OVVM, SNADS, MHS, Lotus Notes, Lotus cc:Mail, Microsoft Mail,
Microsoft Exchange, FAX, Telephone Access, and a generic API
gateway.
GroupWise Addressing The address of every object in the system is known by
its domain name, post office name, and user ID (equivalent to Alias). A fully
qualified GroupWise address is in the following format:
domain.postoffice.userid
How GroupWise Replicates Directory Information- When a GroupWise object is created, modified, or deleted in
NetWare Administrator, the change is written first to NDS.
- In GroupWise 5.0 to 5.2, the ADA monitors activity in NDS
and when it detects a change to a GroupWise object, it:
- Makes changes to the local GroupWise domain database.
- Then replicates that change to all the post offices
within the local domain.
- And finally replicates the change to all other domains
that it is directly connected to.
- If the local domain is a secondary domain, the change is
written to the local database, but it is flagged as "unsafe" until the change
can be written and accepted by the primary domain database.
- GroupWise 5.5 performs directory replication the same way,
only it is the MTA that monitors NDS for changes to GroupWise objects. All ADA
functions are combined into the MTA and POA in GroupWise 5.5.
Back to TopDomain Directory Structure
A GroupWise domain is identified by a set of databases and folders. In other
words, "A domain IS where the domain database (Wpdomain.db) is." The
implications here are that there can be multiple domains on a single server.
The same holds true for post offices. The directory store (or "Address Book")
for the domain is a database named Wpdomain.db. It is typically found in a
folder called Wpdomain, although the root folder of the domain can be named
virtually anything.
NOTE: Because GroupWise includes both Microsoft Windows NT Server and
Novell NetWare NLM agents, a complex GroupWise system can be built out of a
single NetWare server and many servers running Windows NT. The only component
that
must be on a NetWare server is the primary domain and the MTA for that
domain. Because the MTA replicates changes to all post offices and domains that
it knows about, there is no reason why those post offices and domains can't be
on Windows NT servers. That means that secondary domains and post offices can
be entirely located on computers running Windows NT, and that the GroupWise
agent software for Windows NT can be run to service those domains and post
offices. Furthermore, a single NDS tree can accommodate many GroupWise 5.x
systems, so long as each GroupWise system is in its own unique
container.
The directory structure of a GroupWise domain is as
follows:
\WPDOMAIN Root folder for Domain
wphost.dc Dictionary file for GroupWise 4.x post offices
wpdomain.dc Dictionary file for GroupWise 4.x domains
gwdom.dc Dictionary file for GroupWise 5.x domains
gwpo.dc Dictionary file for GroupWise 5.x post offices
wpdomain.db Domain database (the directory store)
\MSLOCAL MTA local folder (advanced messaging functions)
\GWINPROG Priority queues for messages in transit
\MSHOLD MTA holding folder for delayed messages
\DOMAINMS Local MTA holding queues (priority folders)
\DOMxxxx Holding queue for an adjacent domain
\GATxxxx Holding queue for a local gateway
\POSxxxx Holding queue for a local post office
\WPCS Legacy domain MTA software folder
\WPOFFICE Legacy client software distribution point
\WPTOOLS Legacy domain admin tools folder
\WPCSIN MTA input priority queues (from other domains)
\0 Live interactive requests
\1 Other interactive requests
\2 High priority messages
\3 High priority statuses
\4 Normal priority messages
\5 Normal priority statuses
\6 Low priority messages
\7 Low priority statuses
\WPCSOUT MTA output queues (to local domain agents)
\ADS Priority queues for local directory store updates
\<0 .. 7>
\CSS Priority queues for MTA administration messages
\<0 .. 7>
\PROBLEM Dead messages queue
\WPGATE Gateways local to this domain
- The Mslocal\Mshold folder holds messages that are delayed
because the next delivery agent is unable to receive the message. The folder
names take the first three letters of the name of the adjacent entity, as
defined in NetWare Administrator, plus four unique characters "xxxx". For
example, a post office named ACMEPO1 would have a folder name like "ACM3F41".
An adjacent domain named NAMERICA might have a folder name like "NAM88B4". And
a local gateway named GWIA might have a folder name like "GWI5FF2".
- GroupWise clients do not run from the domain's Wpoffice
folder. This was once the point of software distribution, a method of
simplifying client software upgrades. The GroupWise software distribution
folder is now defined as part of the installation of the GroupWise software,
and can be located anywhere on the network.
- You may have noticed the number of "legacy" folders, as
well as the less-than-obvious names for some components. For example, nearly
every folder seems to be named "WP.." instead of "GW..". There's a history to
this naming structure. Before Novell acquired GroupWise from WordPerfect,
Corp., the product was called "WP Office." In WP Office, the MTA component was
called the Connection Server (CS). The ADA component was the Administration
Server (ADS), and the POA component was called the Office Server (OFS). The
name of the product changed from "WP Office" to "Novell GroupWise" between the
4.0 and 4.1 revisions, responding not only to the change in company ownership,
but also the industry shift to call bundled business applications
"Office".
- The "Priority queues" directory structure pervades all of
the GroupWise messaging system and will be discussed in greater depth later in
Part 2 of this series.
- For more details on GroupWise directory structure, see the
Novell online documentation for GroupWise at the following Web site:
GroupWise Post Office Architecture
Whereas the GroupWise domain is the center for administration and message flow
throughout the domain, the GroupWise post office is the center for user
messaging and groupware activities (such as calendaring and scheduling,
document creation and management, and workflow creation and management). The
post office database is almost an exact copy of the domain database, but it is
a read-only copy. No system administration can be performed against the post
office database. On the other hand, no messaging occurs directly at the domain,
only at the post office. GroupWise is unique in this total separation of system
administration from messaging functionality. Most other messaging systems allow
full system administration to be performed against the same server that stores
the messages.
Post Office Directory Structure
Like the GroupWise domain, the GroupWise post office is defined by the set of
files and folders which make up the post office. The directory store (or
"Address Book") is called the post office database. The file name is Wphost.db.
There is no commonly used name for the post office root folder like there is
for the domain.
The directory structure of a GroupWise post office is
as follows:
\POSTOFF Post office root folder
gwpo.dc Dictionary file for post office database
ngwguard.db Guardian database
ngwguard.dc Dictionary file for guardian database
ngwguard.fbk Backup of guardian database
ngwguard.rfl Roll forward file for guardian database recovery
wphost.db Post office database (the directory store)
\GWDMS Document management root folder
\OFFILES Root folder for message attachments
\F
\FD0
\FD1
. 248 folders (the bulk of the message store)
.
.
\FDF6
\OFMSG Root folder for message databases
msg0.db
msg1.db
.
. Up to 25 message databases
.
msg24.db
\OFUSER Root folder for user databases
userfid.db User database for a single user
pufid.db User database for shared folders (public folders)
\OFVIEWS View templates for client software
\OFWORK Temporary working folders
\WPCSIN MTA input priority queues
<\0 .. \7>
\WPCSOUT MTA output priority queues
\ADS Input queues for directory store updates
<\0 .. \7>
\OFS Input queues for local messages and statuses
<\0 .. \7>
\PROBLEM Dead messages folder
- The Guardian database performs many functions, but its
primary function is to ensure the integrity of the entire message store. As
such, GroupWise 5.x goes to great lengths to protect this database, building in
multiple backups, a roll forward transaction log, and frequent error checking.
In short, GroupWise 5.x will not function properly without it. For details on
the Guardian database, see the following Web site:
- The templates for viewing GroupWise messages, which are
contained in the Ofviews folder, are required by the client software for proper
functioning. These view files are similar in concept to Outlook Forms. In
GroupWise 4.x, a utility for creating personalized views came standard with
every installation.
- GroupWise encrypts all messages during both the message
transfer process and the message storage process. The encryption algorithm is
proprietary and very secure.
Message Store Architecture
GroupWise employs a single-instance message store, just as any modern e-mail
system does, but its implementation is unique: It is a combination of
databases, folders, and files that all work together to store e-mail on the
post office. Whereas Exchange has a single file for all user mailboxes and all
user e-mail on a server (Priv.edb) and another single file for all public
folder content (Pub.edb), GroupWise employs dozens of databases for messages
and hundreds of databases for users. In Microsoft Mail, user mailbags,
messages, and attachments are all stored in separate folders. GroupWise is the
same in many ways.
User Databases:- Each GroupWise user has his or her own database. The
database stores pointers to messages in the message databases, as well as all
user preferences.
- The user database file name is in the format:
UserFID.db
where the FID is a unique user file
ID. You can determine a user's file ID by viewing GroupWise account properties
for the user in NetWare Administrator. - All user databases are stored in the Postoff\Ofuser
folder.
- User databases are only created when they are first
accessed, either by a user logging on for the first time, or by the user
receiving a message for the first time. In other words, there may be 25 users
on a post office, but until a message is sent to all 25 users, there will not
be 25 user databases in Postoff\Ofuser.
Message Databases:- GroupWise may have up to 25 message databases. Message
databases store messages that are 2 KB in size or less. The message databases
also store pointers to attachments in the attachments folders.
- The message database file name is in the format
MSGnn.db, where nn
represents a number between 0 and 24.
- All message databases are stored in the Postoff\Ofmsg
folder.
- As with user databases, message databases are not created
until they are first needed.
- Each user in the post office is assigned a message
database, and all messages that the user sends are stored in that assigned
message database. Inbound messages from other post offices are written to the
message database corresponding to that user's assigned message database on the
originating post office.
Attachments Directories:- GroupWise stores all file attachments, and any messages,
headers, or distribution lists that exceed 2 KB in size in a series of folders
called the "attachment folders." Novell says that it does this to enhance
performance of the message databases.
- The attachment folders are all found under Postoff\Offiles.
In GroupWise 4.x there are about 16 of these subfolders. In GroupWise 5.x,
there are hundreds.
- Attachment files are given a random file name and are fully
encrypted with GroupWise proprietary encryption technology.
- The bulk of the GroupWise message store is stored in the
attachments folders.
Shared Folders:- Shared folders are the rough equivalent of public folders
in Exchange. They store pointers to messages just as user databases do. The
difference is in the way the shared folders are managed by the
system.
- A shared folder database file name is in the format
PUxxxxx.db, where xxxxx
is a unique identifier.
- Shared folders are all stored in the Postoff\Ofuser
folder.
Additional Notes About the GroupWise Message Store:- As with Microsoft Exchange Server 5.5, the Novell GroupWise
5.x message store has no limit on its maximum size. However, experience has
shown that when GroupWise message databases get to be several gigabytes in
size, they tend to become very unwieldy and prone to corruption. The Guardian
database goes a long way toward preventing and correcting logical corruption,
but it does not prevent physical corruption of the database.
- Novell GroupWise includes a feature-rich database
maintenance utility with a clean graphical interface that can be run from
NetWare Administrator. It is called "GroupWise Mailbox/Library Maintenance,"
and it allows administrators to check and fix a wide variety of problems with
the message store. Its focus can be as narrow as a single user or as broad as
the entire post office. It is a very effective tool for fixing
problems.
- Novell's philosophy of disaster planning and recovery is to
primarily provide powerful tools for recreating individual databases that have
been accidentally deleted (the GroupWise Mailbox/Library Maintenance tool), and
secondarily provide tools that will allow administrators to back up the message
store. Novell offers a backup utility designed specifically for backing up
GroupWise called Gwbackup. It will back up the GroupWise post office while
users are using it, but it must lock each database while it is backing it up.
This is not a "true" on-line backup, but because the GroupWise message store is
a huge collection of databases and files in many folders, this does not tend to
be much of a problem. However, because GroupWise database technology does not
employ transaction logging, if a disaster occurs that requires administrators
to restore from backup, the best that can be hoped for is to restore all data
to the point of the last backup. All data written to the message store since
the last backup will be lost.
This is the end of Part 1. In Part 2, GroupWise message flow is discussed in
some detail. A glossary also is provided:
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GroupWise Architecture (Part 2): Message Flow and Glossary
In Part 3, the GroupWise API
Gateway is described, and detailed troubleshooting suggestions given:
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GroupWise Architecture (Part 3): API Gateway