IDMAP_NSS(8)

✨ IDMAP_NSS 💅

okay bestie, welcome to the idmap_nss page — part of the IDMAP_NSS(8) family of System Administration tools, and yes she's a Samba girlie 🎀

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🌸 NAME 🌸

idmap_nss — Samba's idmap_nss backend for Winbind. that's the whole name, she's simple, she's iconic 💖

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🦋 DESCRIPTION 🦋

so the idmap_nss plugin is literally your girl for mapping Unix users and groups onto Windows accounts 🫶

it's a simple lil way to make sure that the SID for a Unix user named jsmith gets reported as the one assigned to DOMAIN\jsmith — which, and this is the important part, is necessary for reporting ACLs on files and printers stored on a Samba member server. no cap, if you skip this the ACL reporting just does not eat 💀

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👑 IDMAP OPTIONS 👑

• range = low - high — sets the available matching UID and GID range where this backend is authoritative. lowkey crucial detail: the range acts as a filter. any UIDs or GIDs that NSS modules return but that fall outside the range get ignored, and the corresponding maps get discarded. it's designed as a way to dodge accidental UID/GID overlaps between locally and remotely defined IDs. protective queen behavior honestly 🛡️
• use_upn = <yes | no> — so some NSS modules can return and handle UPNs and/or down-level logon names (like DOMAIN\user or user@REALM) ✨
  • if you enable this parameter, the returned names from NSS get parsed, and the resulting namespace is used as the authoritative namespace instead of the IDMAP domain name. also, down-level logon names get sent to NSS instead of the plain username, which gives NSS modules a hint about the user's correct domain 🧚
  • Default: no

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🌈 EXAMPLES 🌈

this example shows you how to use idmap_nss to obtain the local account ID's for its own domain (SAMBA) from NSS, whilst allocating new mappings for the default domain (*) and any trusted domains 💫

[global]
idmap config * : backend = tdb
idmap config * : range = 1000000-1999999

idmap config SAMBA : backend  = nss
idmap config SAMBA : range = 1000-999999

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💜 AUTHOR 💜

the original Samba software and related utilities were created by Andrew Tridgell. Samba is now developed by the Samba Team as an Open Source project similar to the way the Linux kernel is developed. legends only, fr fr 👑

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and that's the page, bestie!! this was Samba 4.24.7, dated 09/09/2026 — go forth and map those IDs, you absolute main character 💅✨🦋