Document revision date: 30 March 2001

## OpenVMS System Manager's Manual

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### 7.9.2 Setting Up a Project Account with ACL Identifiers

This section describes how to set up a project account that uses access control lists (ACLs) to control access to files shared by members of a project group. See the OpenVMS Guide to System Security for complete details on setting up accounts with ACLs.

How to Perform This Task

You must first add an identifier to the rights database for the project account. Use the AUTHORIZE command ADD/IDENTIFIER to add identifiers to the rights database and then associate users as holders of existing ACL identifiers with the AUTHORIZE command GRANT/IDENTIFIER. All users who hold the project's identifier can use the disk space of the project account.

You can set up the project account so that disk space is charged to the project, rather than to individual users, by assigning the resource attribute to the project identifier.

Example

The following example summarizes the steps for setting up a project account:

1. Set up individual user accounts for each member sharing the project account (as described in Section 7.5 and Section 7.6 on adding a user account).
2. Create the project identifier with the resource attribute and grant it to those users who will have access to the project account. In the example that follows, the project identifier KITE_FLYING is given the resource attribute. This identifier is then granted to users GEORGE and LINDORF.

       $ RUN SYS$SYSTEM:AUTHORIZE
       UAF> ADD/IDENTIFIER KITE_FLYING/ATTRIBUTES=RESOURCE
       {message}
       UAF> GRANT/IDENTIFIER KITE_FLYING GEORGE/ATTRIBUTES=RESOURCE
       {message}
       UAF> GRANT/IDENTIFIER KITE_FLYING LINDORF/ATTRIBUTES=RESOURCE
       {message}
       UAF> EXIT

3. Create the disk quota authorization for the project identifier. For example, the following command invokes SYSMAN and assigns the identifier KITE_FLYING 2000 blocks of disk quota with 200 blocks of overdraft:

       $ RUN SYS$SYSTEM:SYSMAN
       SYSMAN> DISKQUOTA ADD KITE_FLYING/PERMQUOTA=2000/OVERDRAFT=200
       SYSMAN> EXIT

4. Create the project directory. For example, the following DCL command creates the project directory [KITE_FLYING] and establishes the identifier KITE_FLYING as the owner:

       $ CREATE/DIRECTORY [KITE_FLYING]/OWNER=[KITE_FLYING]

5. Set up the necessary ACL and default ACL on the project directory. For example, the following DCL command places an ACL on the directory [KITE_FLYING] that permits any holder of the identifier KITE_FLYING to gain read, write, or execute access to the directory; it also ensures that files created in the directory receive the same ACE (access control list entry) as a default:

       $ SET SECURITY [000000]KITE_FLYING.DIR;1 -
       _$ /ACL=((DEFAULT_PROTECTION,S:RWED,O:RWED,G,W) -
       _$ (IDENTIFIER=KITE_FLYING, ACCESS=READ+WRITE+EXECUTE), -
       _$ (IDENTIFIER=KITE_FLYING,OPTIONS=DEFAULT,ACCESS=READ+WRITE+EXECUTE))

Access must be granted through ACL entries, because the owner identifier of the directory and the files (KITE_FLYING) does not match the UIC of any of the project members; thus, only world access is available through the UIC-based protection mask. The first ACE of the specified ACL gives all project members read, write, and execute access to the directory; the second ACE gives them read, write, and execute access for all files created in the directory.

Note that project members are not allowed to delete (or control) files created by others. However, the members each have complete access to files that they have created in the directory, because the file system supplies an additional default ACL entry that grants to the creator control access plus the access specified in the OWNER field of the UIC-based protection mask. This ACE appears only when the owner of the created file does not match the UIC of the creator.

Thus, when LINDORF creates the file [KITE_FLYING]THURSDAY.TXT, the file receives the following access control list by default:

    (IDENTIFIER=LINDORF,OPTIONS=NOPROPAGATE,
    ACCESS=READ+WRITE+EXECUTE+CONTROL)
    (IDENTIFIER=KITE_FLYING,ACCESS=READ+WRITE+EXECUTE)

You can use the Creator ACE command in the ACL editor to add an extra ACE to the ACL for a file created within the directory to which you assign the Creator ACE. The Creator ACE applies only when the following conditions exist:

- The file being created is not owned by the user identification code (UIC) of the process creating the file.
- The process creating the file does not have system privileges.

See the OpenVMS System Management Utilities Reference Manual and the OpenVMS Guide to System Security for more information about the Creator ACE.

### 7.9.3 Understanding Network Proxy Accounts

A network proxy account allows users on a remote node in a network to access data by way of a local account on your system. Proxy accounts are useful when you want to grant one or more users on a remote node access to specific files, but you do not want to give them a private account on your system. Very often, system managers set up proxy accounts as restricted. You establish and control proxy accounts with the Authorize utility (AUTHORIZE).

With proxy accounts, you can authorize one or more users on a remote node to enter DCL commands that access data from a particular account on your system. Proxy accounts allow remote users to access specific local data (for example, type and print files) without having to log in to your system or use an access control string. Remote users assume the same file access rights as the local account and also receive the default privileges of the local account. The following sections explain the procedures for setting up proxy accounts.

To properly maintain proxy database consistency across all members of a mixed-version OpenVMS Cluster system, you must perform all proxy modifications from either of the following systems:

- A VAX Version 6.1 (or later) system
- An Alpha Version 6.2 (or later) system

This restriction ensures that the NET$PROXY.DAT database is updated with correct proxy information.

For more information about proxy accounts, see the OpenVMS Guide to System Security.

### 7.9.4 Creating Network Proxy Authorization Files

Note This section contains information for network proxies on DECnet Phase IV and DECnet-Plus. For information about proxies and user authentication when using TCP/IP Services, see Compaq TCP/IP Services for OpenVMS Management.

A proxy account permits an authorized user from a remote node to log in to a local node, as if the user owned an account on the local node. Proxy accounts are created and maintained using the Authorize utility (AUTHORIZE). See the OpenVMS System Management Utilities Reference Manual for more information about the Authorize utility.

On OpenVMS systems, the following information is stored in two proxy authorization files, NETPROXY.DAT and NET$PROXY.DAT:

- On systems running DECnet for OpenVMS, both NETPROXY.DAT and NET$PROXY.DAT contain proxy information stored using DECnet VAX node names.
- On systems running DECnet-Plus:
  - NET$PROXY.DAT contains proxy information stored using DECnet-Plus full names.
  - NETPROXY.DAT contains proxy information stored using DECnet-Plus node synonyms.

  Note Deleting either NETPROXY.DAT or NET$PROXY.DAT will result in incorrect functioning of proxy access on systems running DECnet for OpenVMS Phase IV. Also, many applications such as ALL-IN-1 rely on NETPROXY.DAT.

The SYSUAF.DAT file, on your local system, must associate proxy accounts with user accounts. You will probably want to create a "standard access" account in the UAF for proxy accounts. For example, you could create an account named REMOTE_MKT with limited privileges, which allows access to certain data files on your local system.

Suppose you have a group of users on your local system who prepare marketing reports and who rely on input from users on other systems. You would assign the REMOTE_MKT account in SYSUAF.DAT the same group number and default privileges you assign to the local marketing group. In this way, the remote contributors could access any data files that are "owned" by users in your marketing group and that are not protected from group access.

How to Perform This Task

Use the AUTHORIZE command CREATE/PROXY to create and initialize network proxy authorization files:

    UAF> CREATE/PROXY

### 7.9.5 Adding Proxy Accounts

Create a proxy account by adding entries to the network proxy authorization file; these entries equate one or more users on a remote node to users on your home node.

How to Perform This Task

The command syntax for adding a proxy account is as follows:

`ADD/PROXY node::remote-user local-user/DEFAULT [,...]`

You can allow remote users access to up to 16 total local accounts: 1 default proxy account and 15 alternate proxy accounts. Use the /DEFAULT qualifier to specify the default proxy account.

Examples

1. The following command adds a user proxy account:

       UAF> ADD/PROXY HAL::WALTER REMOTE_MKT/DEFAULT,PROXY2,PROXY3

   Assume that you have created three accounts named REMOTE_MKT, PROXY2, and PROXY3 on your home node. The entry in this example permits the user WALTER on remote node HAL to access data by way of the REMOTE_MKT account on your home node. WALTER can access any data from his node that REMOTE_MKT can access locally. To access data through either PROXY2 or PROXY3, WALTER must specify the desired proxy account in the access control string of the DCL command used to perform network file operations.

   Caution Because the remote user receives the same privileges as the local user, do not set up proxy accounts associated with local accounts that have special privilege. Granting remote users such access powers poses a threat to the security of your system.

2. You can specify remote users by user name or, for remote systems that do not recognize the user name syntax, by UIC. The following example allows the user associated with the UIC [360,54] on remote node RSTS32 proxy access to the GENERIC account on the local node:

       UAF> ADD/PROXY RSTS32::[360,54] GENERIC/DEFAULT

3. A number of your users might have accounts on a remote node and require ready access to their local files. You can create a network proxy authorization file record that grants access to each of them, provided the user name on your system is the same as the user name on the remote node. The following form of the ADD/PROXY command adds such a record:

       UAF> ADD/PROXY HAL::* */DEFAULT

   This command authorizes any user on the remote node HAL to access any account with the same user name on your system.
   Similarly, you might want to permit this sort of access for just one user:

       UAF> ADD/PROXY HAL::BARBARA */DEFAULT

4. On systems running DECnet-Plus, the system adds network proxies to the network proxy authorization file NET$PROXY.DAT using DECnet-Plus full names. For example:

       UAF> ADD/PROXY RUBY::DELAPORT DELAPORT/DEFAULT,SYSTEM
       %UAF-I-NAFADDMSG, proxy from OMNI:.US.RUBY::DELAPORT to DELAPORT added
       %UAF-I-NAFADDMSG, proxy from OMNI:.US.RUBY::DELAPORT to SYSTEM added

   This example adds proxy access from RUBY::DELAPORT to the local accounts DELAPORT (the default) and SYSTEM.
   The system additionally stores node synonyms in NETPROXY.DAT for use by DECnet for OpenVMS and for backward compatibility for layered products.

### 7.9.6 Removing Proxy Accounts

To remove proxy accounts, use the AUTHORIZE command REMOVE/PROXY; for example:

    UAF> REMOVE/PROXY RUBY::DELAPORT SYSTEM

This command removes proxy access from RUBY::DELAPORT to the local SYSTEM account.

### 7.9.7 Displaying Proxy Accounts

To display proxy accounts, use the AUTHORIZE command SHOW/PROXY. This command displays only the first 255 characters of the node name, although the command can handle a maximum of 1024 characters.

The following examples assume that proxy access from RUBY::DELAPORT to the local account DELAPORT has been added to the network proxy authorization file as the default. (The second example shows the DECnet-Plus equivalent of RUBY::DELAPORT.)

Examples

1. On systems running DECnet for OpenVMS, the system displays the following type of information:

       UAF> SHOW/PROXY *::*

       RUBY::DELAPORT
            DELAPORT (D)

   (D) indicates that DELAPORT is the default proxy.
2. On systems running DECnet-Plus, the system displays information in full names format:

       UAF> SHOW/PROXY *::*

       OMNI:.US.RUBY::DELAPORT
           DELAPORT (D)

   (D) indicates that DELAPORT is the default proxy.
   You can display information in the old format NETPROXY.DAT database by using the /OLD qualifier with the SHOW/PROXY command; for example:

       UAF>  SHOW/PROXY/OLD *::*

### 7.9.8 Controlling Proxy Logins

Whenever a proxy login request occurs, the system verifies that proxy access on the participating nodes is enabled. (By default, both incoming and outgoing proxy access is enabled for each node.)

On systems running DECnet for OpenVMS, you can change proxy access or disable it totally by using the Network Control Program (NCP). The DECnet for OpenVMS Networking Manual describes how to use NCP to control proxy access.

On systems running DECnet-Plus software, you can change proxy access by using the Network Control Language utility (NCL). The DECnet-Plus Network Control Language Reference manual describes how to use NCL.

Note For information about proxies and user authentication when using TCP/IP Services, see the Compaq TCP/IP Services for OpenVMS Management.

## 7.10 Managing Mail

When managing user accounts, you might have to manage a user's mail account. For example, you may want to perform the following tasks:

- Change a user's mail profile; for example, change a user name or specify a default print queue for the account
- Set a forwarding address for a user who has moved to another location
- Disable a user's account from receiving mail
- Customize a user's mail environment by setting flags in a user's UAF record

The following sections explain how to perform all of these tasks.

### 7.10.1 Modifying a User Record

All users can modify and display information about their own records using various SET and SHOW commands available within Mail. These commands access SYS$SYSTEM:VMSMAIL_PROFILE.DATA, which is a single-key indexed sequential file containing information for each user.

With SYSNAM, you can change the mail forwarding address for a user (including one without an account) on the system with the Mail utility command SET FORWARD/USER=user.

### 7.10.2 Removing a User Record

Typically, once you have deleted a user's record in the UAF, you will also want to remove that user's information from the user profile database. You can remove a record from the user profile database with the REMOVE command.

### 7.10.3 AUTHORIZE Flags and Mail

Certain flags set in a user's UAF record can affect the user's Mail environment. You can set the appropriate flags in a user account by specifying the following flags with the /FLAGS qualifiers using AUTHORIZE:

Flag | Meaning
--- | ---
[NO]DISNEWMAIL | Enables or disables the display of the new mail count when the user logs in to the system.
[NO]DISMAIL | Allows or restricts the receipt of new mail.

## 7.11 Managing System Resources

This section contains detailed descriptions of the resource control attributes you can assign to a user process when creating a record in the UAF.

### 7.11.1 Understanding Pages and Pagelets

VAX and Alpha systems allocate and deallocate memory for processes in units called pages. A page on a VAX system is 512 bytes. On Alpha systems, the page size will be one of four values: 8KB (8192 bytes), 16KB, 32KB, or 64KB. A particular Alpha system will implement only one of the four page sizes and the initial set of machines use an 8KB page.

In most cases, Alpha systems present to users, and accept from users, units of memory in a 512-byte quantity called a pagelet. Thus, one pagelet is the same size as one VAX page. Also, on an Alpha 8KB computer, 16 pagelets equal 1 Alpha page. The following conversion table shows the relationship between pages, pagelets, and bytes:

    One Alpha pagelet = one VAX page      = 512 bytes
    One Alpha page    = 16 Alpha pagelets = 16 VAX pages = 8192 bytes

Authorize utility commands, parameters, and default values are identical. However, the default values for process quotas related to memory use might be inappropriate for some Alpha system users.

See A Comparison of System Management on OpenVMS AXP and OpenVMS VAX for more information about Alpha system management. (This manual has been archived but is avalable on the OpenVMS Documentation CD-ROM.)

### 7.11.2 Setting Limits on System Resources

Each system user is limited in the consumption of such resources as system memory, volatile (pagefile) disk space, number of processes, and I/O requests. You set limits when you create an account for the user with the Authorize utility.

Limits control the way in which a process shares its allotment of a resource with the subprocesses it creates. In addition to restricting the number of processes that a single user or account has at any given time, the system uses four types of limits for sharing resources. Table 7-1 describes these limits.

When you create an account, you assign values to the limits shown in Table 7-8. These limits are described in the following sections. Usually, you simply assign the default values for these limits. However, see the OpenVMS Performance Management for a discussion of how to evaluate and adjust the limits in the context of performance optimization strategies.

Table 7-8 summarizes each of these limits, the value supplied in the UAF record for the SYSTEM and DEFAULT accounts, and the type of limit.

Table 7-8 Limits and Suggested Values for SYSTEM and DEFAULT Accounts
Limit | VAX SYSTEM Value | VAX DEFAULT Value | Alpha SYSTEM Value | Alpha DEFAULT Value | Type1 | Description
--- | --- | --- | --- | --- | --- | ---
ASTlm | 50 | 0 | 250 | 250 | N | AST queue limit
BIOlm | 40 | 40 | 150 | 150 | N | Buffered I/O count limit
Bytlm | 32768 | 32768 | 64000 | 64000 | P | Buffered I/O byte count limit
CPU | 0 | 0 | 0 | 0 | D | CPU time limit (0 = no limit)
DIOlm | 40 | 40 | 150 | 150 | N | Direct I/O count limit
Enqlm | 300 | 200 | 2000 | 2000 | P | Enqueue quota
Fillm | 300 | 300 | 100 | 100 | P | Open file limit
JTquota | 4096 | 4096 | 4096 | 4096 | P | Initial byte quota for jobwide logical name table
Maxacctjobs | 0 | 0 | 0 | 0 | S | Maximum active processes for a single account (0 = no limit)
Maxdetach | 0 | 0 | 0 | 0 | S | Maximum detached processes for a single user name (0 = no limit)
Maxjobs | 0 | 0 | 0 | 0 | S | Maximum active processes for a single user name (0 = no limit)
Pgflquo | 20480 pages | 32768 pages | 50000 pagelets | 50000 pagelets | P | Page file limit
Prclm | 10 | 2 | 10 | 8 | P | Subprocess creation limit
TQElm | 30 | 40 | 20 | 10 | P | Timer queue entry limit
WSdef 2 | 256 pages | 256 pages | 2000 pagelets | 2000 pagelets | N | Default working set size
WSextent 2 | 40960 pages | 1024 pages | 16384 pagelets | 16384 pagelets | N | Working set extent
WSquo 2 | 512 pages | 512 pages | 4000 pagelets | 4000 pagelets | N | Working set quota

1D=deductible, N=nondeductible, P=pooled, S=systemwide
2For this limit, LOGINOUT uses the larger value of the AUTHORIZE quota for this account or the corresponding system parameter PQL_MWSDEF, PQL_MWSEXTENT, or PQL_MWSQUO.

Table 7-9 shows the names and descriptions of the SYSTEM and DEFAULT accounts whose values are listed in Table 7-8. The /EXPIRATION qualifier is also described in Table 7-9.

Table 7-9 Descriptions of SYSTEM and DEFAULT Accounts
Account | Description
--- | ---
AST Queue Limit (ASTlm) | Limits the sum of the following amounts: The number of asynchronous system trap (AST) requests that a user's process can have outstanding at one time The number of scheduled wakeup requests that a user's process can have outstanding at one time This limit affects all system services that accept an AST address as an argument, and the Schedule Wakeup ($SCHDWK) system service. If the deferred write option (DFW) is enabled, the number of ASTs used per file is equal to 1, plus the number of record streams, plus the multibuffer count. Otherwise, the number is 1 plus the number of record streams.
Buffered I/O Count Limit (BIOlm) | Limits the number of outstanding buffered I/O operations permitted for a user's process. In a buffered I/O operation, the data transfer takes place from an intermediate buffer in the system pool, not from a process-specified buffer. Buffered operations for a user process include terminal I/O, file system and network I/O, card reader input, and unspooled printer output. During a buffered I/O operation, the pages containing the process-specified buffer need not be locked in memory.
Buffered I/O Byte Count Limit (Bytlm) | Limits the amount of buffer space that a user's process can use. This buffer space is used for buffered I/O operations and for the creation of temporary mailboxes. It also limits the number of mapping windows the user can create as segmented (or cathedral) windows. Cathedral windows are primarily useful for reducing the overhead required to read large files.
CPU Time Limit (CPU) | Limits the amount of CPU time that a user's process can use per session. The time must be specified in abbreviated delta format hh:mm:ss.cc. CPU is a deductible limit with a suggested typical value of 0 (no limit) but the value applies only to this instance or to other instances of the user's processes. CPU is not cumulative across separate sessions or batch jobs.
Direct I/O Count Limit (DIOlm) | Limits the number of outstanding direct I/O operations permitted to a user's process. In a direct I/O operation, the data transfer takes place directly from a process-specified buffer. Direct I/O operations for a user process typically include disk and tape I/O. The pages containing this buffer are locked in memory by the operating system during the direct I/O operation. DIOlm is a nondeductible limit.
Enqueue Quota (Enqlm) | Limits the number of locks a process (and its subprocesses) can own. OpenVMS Record Management Services (RMS) uses the Lock Management facility to synchronize shared file access, global buffers, and record locks. Because RMS removes one lock for every shared file, local buffer, global buffer section, and outstanding record lock, users who expect to perform large amounts of RMS file sharing should have Enqlm set to a large value. If your process performs extensive RMS file sharing without sufficient enqueue quota, you could receive the SS$_EXENQLM error message. Furthermore, if your system performs extensive RMS file sharing and the value of the LOCKIDTBL system parameter is too low, you could receive the SS$_NOLOCKID error message. Note that whenever you increase the value of LOCKIDTBL, you might have to increase the value of the RESHASHTBL system parameter. (See the OpenVMS System Management Utilities Reference Manual.) For shared files, the value of Enqlm should represent the number of files open as shared multiplied by the number of locks per process per file. If you use the default multibuffer counts, estimate the number of locks as 4 for indexed sequential files and 3 for relative files. If you use a value other than the default value for the multibuffer counts, estimate the number of locks per process per file as 1 per file, plus the multibuffer count for that file, plus the number of records locked, which is usually one. Prior to OpenVMS Version 7.1, the limit for Enqlm was 32767. Setting Enqlm to this former maximum value automatically scales Enqlm internally to the architectural maximum value. Thus, in effect, the process has an unlimited enqueue quota but does not need the privilege to ignore quotas. Use the DCL command SHOW RMS_DEFAULT to display the default multibuffer counts. Enqlm is a pooled limit.
Expiration Date and Time (EXPIRATION) | Qualifier that specifies the expiration date and time of the account. The /NOEXPIRATION qualifier removes the expiration date on the account or resets the expiration time for expired accounts. The /EXPIRATION qualifier does not affect the expiration of passwords.
Open File Limit (Fillm) | Limits the number of files that a user's process can have open at one time. This limit includes the number of network logical links that can be active at the same time. Fillm is a pooled limit. Note that each open file also requires at least 96 bytes of Bytlm.
Job Table Quota (JTquota) | Specifies the initial byte quota with which the jobwide logical name table is to be created. JTquota is a pooled quota.
Maximum Account Jobs Limit (Maxacctjobs) | Specifies the maximum number of batch, interactive, and detached processes that might be active at one time for all users of a single account. Maxacctjobs is a systemwide limit.
Maximum Detached Processes Limit (Maxdetach) | Specifies the maximum number of detached processes with the cited user name that can be active at one time. MAXDETACH can also be used to control the number of virtual terminals a user can have. To prevent the user from creating detached processes, specify the keyword NONE. By default, a user has a value of 0, which represents an unlimited number. Maxdetach is a systemwide limit.
Maximum Process Jobs Limit (Maxjobs) | Specifies the maximum number of interactive, batch, and detached processes that can be active at one time for the cited user name. Maxjobs is a systemwide limit.
Page File Limit (Pgflquo) | Limits the number of pages that the user's process can use in the system page file. The page file provides temporary disk storage for pages forced out of memory by a memory management operation. Pgflquo limits the total virtual address space that can be created using the Create Virtual Address Space ($CRETVA) or Expand Program/Control Region ($EXPREG) system services. Pgflquo is a pooled limit.
Subprocess Creation Limit (Prclm) | Limits the number of subprocesses a user's process can create. The process created when a user logs in to the system can in turn create subprocesses. These subprocesses are all accountable to the user and share the resources allotted to the initial process. Prclm is a pooled limit.
Timer Queue Entry Limit (TQElm) | Limits either of the following amounts: The number of entries that a user's process can have in the timer queue The number of temporary common event flag clusters that a user's process can have This limit does not govern the creation of permanent event flag clusters. Timer queue entries are used in time-dependent scheduling; common event flags are used in synchronizing activities among groups of cooperating processes. TQElm is a pooled limit.
Default Working Set Size (WSdef) | Sets the initial working set size limit for a user's process. WSdef is a nondeductible limit. If the value specified exceeds the value of WSquo, the lesser value is used.
Working Set Extent (WSextent) | Specifies the maximum size to which a user's physical memory usage can grow, independent of the system load. This enlargement of the physical memory for a user is accomplished by the Adjust Working Set Limit ($ADJWSL) system service, and is normally done for the user by the operating system in response to heavy page faulting by the user. WSextent is a nondeductible quota. This value should always be greater than or equal to WSquo. The value is controlled by the system parameter WSMAX. Note that PQL_MWSEXTENT will overwrite the account's value for WSextent if PQL_MWSEXTENT is larger than WSextent.
Working Set Quota (WSquo) | Specifies the working set quota. This is the maximum amount of physical memory a user process can lock into its working set. It also represents the maximum amount of swap space that the system reserves for this process and the maximum amount of physical memory that the system allows the process to consume if the systemwide memory demand is significant. This parameter guarantees the user that the number of physical pages specified will be available. The maximum value of WSquo is 64K pages. WSquo is a nondeductible quota. This value should be greater than or equal to WSdef. The value is capped by the system parameter WSMAX.

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