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34 client side callback daemon
37 .Op Fl p Ar port_number
38 .Op Fl P Ar client_principal
41 runs on a client using
43 to handle callback requests from the NFSv4 server.
46 is running, NFSv4 mounts will still work, but the server will never issue
47 Open Delegations to the client.
49 One callback server and one master server
52 The following options are available:
54 .It Fl p Ar port_number
55 Specifies what port# the callback server should use.
56 .It Fl P Ar client_principal
57 Specifies the host based principal name to be used as the target for
58 callbacks over RPCSEC_GSS. For KerberosV, it must be in the client's
60 This client_principal should be the same one specified by the
62 argument being used by nfsv4 mounts.
63 If you do not specify this argument, callbacks will still work over AUTH_SYS,
64 which is what many extant servers use even for RPCSEC_GSS mounts, as of 2009.
68 .Dq Li "nfscbd -p 7654 -P root"
69 starts the daemon to handle callbacks on port# 7654 and is using the host based
70 principal root@<client-host>.<dns-domain> as the callback target.
73 listens for service requests at the port
74 defined by NFSV4_CBPORT in /usr/include/fs/nfs/nfs.h, unless
77 For more information on what callbacks and Open Delegations do, see
78 .%T "Network File System (NFS) Version 4 Protocol" ,
86 First introduced with the experimental nfs client for NFSv4 support in 2009.