SMB Users Unable to Write to UNIX Security‑Style CIFS Shares After LDAP Integration

• ONTAP 9
• CIFS/SMB
• LDAP

• After LDAP/LDAPS (port 636) is configured for name‑service lookups, users getting "ACCESS DENIED" when writing or creating file/folders. Read access working as expected. 

• SMB user mapped to default UNIX user `pcuser`

::> secd authentication show-creds -vserver <SVM> -win-name <DOMAIN\user>

UNIX UID: pcuser
Windows User: <DOMAIN\user>
GID: pcuser
Supplementary GIDs:
pcuser

• Underlying directory uses UNIX 755 permissions

::> vserver security file-directory show -vserver <SVM> -path /vol/home/user

UNIX Mode Bits: 755
UNIX Mode Bits in Text: rwxr-xr-x
UNIX User Id: <user_uid>
UNIX Group Id: <user_gid>

• Effective permissions show no write access

::> vserver security file-directory show-effective-permissions -vserver <SVM> -win-user-name <user> -path /vol/home/user

Effective File or Directory Permission: 0x1200b9
Read
Read EA
Write EA
Execute
Read Attributes
Read Control
Synchronize

• ns-switch includes LDAP before NIS/files

::> vserver services name-service ns-switch show -vserver <SVM> -database passwd,group
passwd: files,ldap,nis
group : files,ldap,nis

• LDAP cannot resolve UNIX users (no RFC2307 attributes)

::> vserver services name-service getpwbyname -vserver <SVM> -username <user>

Error: command failed: Failed to resolve <user>.
Reason: Entry not found for "username: <user>".

• Explicit win → unix name‑mapping rules were properly configured