---
name: "nisplus_table"
section: "5"
platform: "linux"
package: "postfix"
version: "3.11.7-1"
release: "Arch Linux 2026-11-01"
platforms: ["linux", "macos"]
url: "https://new.carta.tech/nisplus_table"
---

# nisplus\_table(5)

Postfix NIS+ client

## NAME

nisplus\_table - Postfix NIS+ client

## SYNOPSIS

```
postmap -q "string" "nisplus:[name=%s];name.name."
postmap -q - "nisplus:[name=%s];name.name." <inputfile
```

## DESCRIPTION

The Postfix mail system uses optional lookup tables. rewriting or mail routing. These tables are usually in **lmdb:**, **cdb:**, **hash:**, or **dbm:** format.

Alternatively, lookup tables can be specified as NIS+ databases. To find out what types of lookup tables your Postfix system supports use the "**postconf -m**" command.

To test Postfix NIS+ lookup tables, use the "**postmap -q**" command as described in the SYNOPSIS above.

## QUERY SYNTAX

```

```

Most of the NIS+ query is specified via the NIS+ map name. The general format of a Postfix NIS+ map name is as follows:

    **nisplus:\[***name***=%s\];***name.name.name***.:***column*

Postfix NIS+ map names differ from what one normally would use with commands such as **niscat**:

- •

  With each NIS+ table lookup, "**%s**" is replaced by a version of the lookup string.  There can be only one "**%s**" instance in a Postfix NIS+ map name.

- •

  Postfix NIS+ map names use "**;**" instead of "**,**", because the latter character is special in the Postfix main.cf file.  Postfix replaces "**;**" characters in the map name by "**,**" before making NIS+ queries.

- •

  The ":*column*" part in the NIS+ map name is not part of the actual NIS+ query. Instead, it specifies the number of the table column that provides the lookup result. When no ":*column*" is specified the first column (1) is used.

## EXAMPLE

```

```

A NIS+ aliases map might be queried as follows:

```
    alias_maps = dbm:/etc/mail/aliases,
        nisplus:[alias=%s];mail_aliases.org_dir.$mydomain.:1
```

This queries the local aliases file before the NIS+ file.

## SEE ALSO

```
postmap(1), Postfix lookup table manager
```

## README FILES

```

```

Use "**postconf readme\_directory**" or "**postconf html\_directory**" to locate this information.

```
DATABASE_README, Postfix lookup table overview
```

## LICENSE

```

```

The Secure Mailer license must be distributed with this software.

## AUTHOR(S)

```
Geoff Gibbs
UK-HGMP-RC
Hinxton
Cambridge
CB10 1SB, UK
Adopted and adapted by:
Wietse Venema
IBM T.J. Watson Research
P.O. Box 704
Yorktown Heights, NY 10598, USA
Wietse Venema
Google, Inc.
111 8th Avenue
New York, NY 10011, USA
```