---
name: "nfs4mapid"
section: "8"
platform: "macos"
package: "NFS"
version: "343.100.5"
release: "macOS 26.5"
platforms: ["macos"]
url: "https://new.carta.tech/nfs4mapid"
---

# nfs4mapid(8)

shows NFSv4 mappings from uids or gids to over the wire string names and string names to uids or gids.

## NAME

**nfs4mapid** – shows NFSv4 mappings from uids or gids to over the wire string names and string names to uids or gids.

## SYNOPSIS

**nfs4mapid** \[**-G**\] *string* *name*

**nfs4mapid** \[**-G**\] *GUID*

**nfs4mapid** **-u** *uid*

**nfs4mapid** **-g** *gid*

## DESCRIPTION

In the first form, **nfs4mapid** shows translations from NFSv4 string representations of users, and with the  **-G** option, groups, to the corresponding local uids and gids. In the second form shows the translations from opendirectoy GUIDS to NFSv4 strings. The well known strings names (which are distinguished by a trailing  ‘@’ ), such as "OWNER@" and "GROUP@" are represented locally by GUIDs and may not map to uids or gids. To map those GUIDS to NFSv4 strings use this form. The first form can be used to map the well known ids to GUIDs. **nfs4mapid** does this by looking at the trailing  ‘@’ sign. Note that NFSv4 well known names are always groups and are used in ACEs. In the third form, it shows the mapping from uids to the NFSv4 user@domain form. Similarly, in the last form it shows the mapping from gids to the NFSv4 group@domain. **nfs4mapid** will also show the intermediate GUID translation if used. The  NFSv4 domain name should be set with dscl(1). See opendirectory(8) for instructions.

- **-G**

  Map an NFSv4 string to a gid.

- **-u**

  Map a uid to an NFSv4 user@domain string.

- **-g**

  Map a gid to an NFSv4 group@domain string.

## NOTES

**nfs4mapid** uses a privileged nfs client system call to pass the translation request down to the kernel, so results will be the same as a request coming from an NFSv4 server. Because of this, **nfs4mapid** must be run with root privileges.

## SEE ALSO

dscl(1), [nfs(5)](/nfs/5.md), opendirectoryd(8), [mount\_nfs(8)](/mount_nfs/8.md),

## HISTORY

The **nfs4mapid** utility first appeared in OSX 10.10