RPC.IDMAPD(8) System Manager's Manual RPC.IDMAPD(8)
NAME
rpc.idmapd — NFSv4 ID <-> Name Mapper
SYNOPSIS
rpc.idmapd [-h] [-f] [-v] [-C] [-S] [-p path] [-c path]
DESCRIPTION
rpc.idmapd is the NFSv4 ID <-> name mapping daemon. It provides func-
tionality to the NFSv4 kernel client and server, to which it communi-
cates via upcalls, by translating user and group IDs to names, and vice
versa.
The system derives the user part of the string by performing a password
or group lookup. The lookup mechanism is configured in
/etc/idmapd.conf
By default, the domain part of the string is the system's DNS domain
name. It can also be specified in /etc/idmapd.conf if the system is
multi-homed, or if the system's DNS domain name does not match the name
of the system's Kerberos realm.
When the domain is not specified in /etc/idmapd.conf the local DNS
server will be queried for the _nfsv4idmapdomain text record. If the
record exists that will be used as the domain. When the record does not
exist, the domain part of the DNS domain will used.
Note that on more recent kernels only the NFSv4 server uses rpc.idmapd.
The NFSv4 client instead uses nfsidmap(8), and only falls back to
rpc.idmapd if there was a problem running the nfsidmap(8) program.
The options are as follows:
-h Display usage message.
-v Increases the verbosity level (can be specified multiple
times).
-f Runs rpc.idmapd in the foreground and prints all output to
the terminal.
-p path Specifies the location of the RPC pipefs to be path. The
default value is "/var/lib/nfs/rpc_pipefs".
-c path Use configuration file path. This option is deprecated.
-C Client-only: perform no idmapping for any NFS server, even
if one is detected.
-S Server-only: perform no idmapping for any NFS client, even
if one is detected.
CONFIGURATION FILES
rpc.idmapd recognizes the following value from the [general] section of
the /etc/nfs.conf configuration file:
pipefs-directory
Equivalent to -p.
All other settings related to id mapping are found in the
/etc/idmapd.conf configuration file.
EXAMPLES
rpc.idmapd -f -vvv
Runs rpc.idmapd printing all messages to console, and with a verbosity
level of 3.
FILES
/etc/idmapd.conf, /etc/nfs.conf
SEE ALSO
idmapd.conf(5), nfs.conf(5), nfsidmap(8)
AUTHORS
The rpc.idmapd software has been developed by Marius Aamodt Eriksen
⟨marius@citi.umich.edu⟩.
Debian February 3, 2003 RPC.IDMAPD(8)
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