NFSSTAT(8) Maintenance Commands and Procedures NFSSTAT(8)
nfsstat - NFS statistics
nfsstat [-cnrsza] [-T u | d ] [-v version] [interval [count]]
nfsstat -m [pathname]...
nfsstat displays statistical information about the NFS and RPC
(Remote Procedure Call), interfaces to the kernel. It can also be
used to reinitialize this information. If no options are given the
default is as follows:
nfsstat -csnra
The default displays everything, but reinitializes nothing.
-a
Display NFS_ACL information.
-c
Display client information. Only the client side NFS, RPC, and
NFS_ACL information is printed. Can be combined with the -n, -r,
and -a options to print client side NFS, RPC, and NFS_ACL
information only.
-m [pathname...]
Display statistics for each NFS mounted file system. If pathname
is not specified, displays statistics for all NFS mounted file
systems. If pathname is specified, displays statistics for the
NFS mounted file systems indicated by pathname.
This includes the server name and address, mount flags, current
read and write sizes, the retransmission count, the attribute
cache timeout values, failover information, and the timers used
for dynamic retransmission. The dynamic retransmission timers are
displayed only where dynamic retransmission is in use. By
default, NFS mounts over the TCP protocols and NFS Version 3
mounts over either TCP or UDP do not use dynamic retransmission.
If you specify the -m option, this is the only option that
nfsstat uses. If you specify other options with -m, you receive
an error message alerting that the -m flag cannot be combined
with other options.
-n
Display NFS information. NFS information for both the client and
server side are printed. Can be combined with the -c and -s
options to print client or server NFS information only.
-r
Display RPC information.
-s
Display server information.
-T u | d
Display a time stamp.
Specify u for a printed representation of the internal
representation of time. See time(2). Specify d for standard date
format. See date(1).
-v version
Specify which NFS version for which to print statistics. When
followed by the optional version argument, (2|3|4), specifies
statistics for that version. By default, prints statistics for
all versions.
-z
Zero (reinitialize) statistics. This option is for use by the
super user only, and can be combined with any of the above
options to zero particular sets of statistics after printing
them.
The following operands are supported:
count
Display only count reports
interval
Report once each interval seconds.
pathname
Specify the pathname of a file in an NFS mounted file system for
which statistics are to be displayed.
The server RPC display includes the following fields:
badcalls
The total number of calls rejected by the RPC layer (the sum of
badlen and xdrcall as defined below).
badlen
The number of RPC calls with a length shorter than a minimum-
sized RPC call.
calls
The total number of RPC calls received.
dupchecks
The number of RPC calls that looked up in the duplicate request
cache.
dupreqs
The number of RPC calls that were found to be duplicates.
nullrecv
The number of times an RPC call was not available when it was
thought to be received.
xdrcall
The number of RPC calls whose header could not be XDR decoded.
The server NFS display shows the number of NFS calls received (calls)
and rejected (badcalls), and the counts and percentages for the
various calls that were made.
The server NFS_ACL display shows the counts and percentages for the
various calls that were made.
The client RPC display includes the following fields:
calls
The total number of RPC calls made.
badcalls
The total number of calls rejected by the RPC layer.
badverfs
The number of times the call failed due to a bad verifier in the
response.
badxids
The number of times a reply from a server was received which did
not correspond to any outstanding call.
cantconn
The number of times the call failed due to a failure to make a
connection to the server.
cantsend
The number of times a client was unable to send an RPC request
over a connectionless transport when it tried to do so.
interrupts
The number of times the call was interrupted by a signal before
completing.
newcreds
The number of times authentication information had to be
refreshed.
nomem
The number of times the call failed due to a failure to allocate
memory.
retrans
The number of times a call had to be retransmitted due to a
timeout while waiting for a reply from the server. Applicable
only to RPC over connection-less transports.
timeouts
The number of times a call timed out while waiting for a reply
from the server.
timers
The number of times the calculated time-out value was greater
than or equal to the minimum specified time-out value for a call.
The client NFS display shows the number of calls sent and rejected,
as well as the number of times a CLIENT handle was received (clgets),
the number of times the CLIENT handle cache had no unused entries
(cltoomany), as well as a count of the various calls and their
respective percentages.
The client NFS_ACL display shows the counts and percentages for the
various calls that were made.
The -m option includes information about mount flags set by mount
options, mount flags internal to the system, and other mount
information. See mount_nfs(8).
The following mount flags are set by mount options:
grpid
System V group id inheritance.
hard
Hard mount.
intr
Interrupts allowed on hard mount.
llock
Local locking being used (no lock manager).
noac
Client is not caching attributes.
nointr
No interrupts allowed on hard mount.
nocto
No close-to-open consistency.
retrans
NFS retransmissions.
rpctimesync
RPC time sync.
rsize
Read buffer size in bytes.
sec
sec has one of the following values:
dh
des-style authentication (encrypted timestamps).
krb5
kerberos v5-style authentication.
krb5i
kerberos v5-style authentication with integrity.
krb5p
kerberos v5-style authentication with privacy.
none
No authentication.
short
Short hand UNIX-style authentication.
sys
UNIX-style authentication (UID, GID).
soft
Soft mount.
timeo
Initial NFS timeout, in tenths of a second.
wsize
Write buffer size in bytes.
The following mount flags are internal to the system:
acl
Server supports NFS_ACL.
down
Server is down.
dynamic
Dynamic transfer size adjustment.
link
Server supports links.
mirrormount
Mounted automatically by means of the mirrormount mechanism.
printed
"Not responding" message printed.
readdir
Use readdir instead of readdirplus.
symlink
Server supports symbolic links.
The following flags relate to additional mount information:
proto
Protocol.
vers
NFS version.
The -m option also provides attribute cache timeout values. The
following fields in -m output provide timeout values for attribute
cache:
acdirmax
Maximum seconds to hold cached directory attributes.
acdirmin
Minimum seconds to hold cached directory attributes.
acregmax
Maximum seconds to hold cached file attributes.
acregmin
Minimum seconds to hold cached file attributes.
The following fields in -m output provide failover information:
currserver
Which server is currently providing NFS service. See the for
additional details.
failover
How many times a new server has been selected.
noresponse
How many times servers have failed to respond.
remap
How many times files have been re-evaluated to the new server.
The fields in -m output shown below provide information on dynamic
retransmissions. These items are displayed only where dynamic
retransmission is in use.
cur
Current backed-off retransmission value, in milliseconds.
dev
Estimated deviation, in milliseconds.
srtt
The value for the smoothed round-trip time, in milliseconds.
The following exit values are returned:
0
Successful completion.
>0
An error occurred.
attributes(7), mount_nfs(8)
June 16, 2009 NFSSTAT(8)
NAME
nfsstat - NFS statistics
SYNOPSIS
nfsstat [-cnrsza] [-T u | d ] [-v version] [interval [count]]
nfsstat -m [pathname]...
DESCRIPTION
nfsstat displays statistical information about the NFS and RPC
(Remote Procedure Call), interfaces to the kernel. It can also be
used to reinitialize this information. If no options are given the
default is as follows:
nfsstat -csnra
The default displays everything, but reinitializes nothing.
OPTIONS
-a
Display NFS_ACL information.
-c
Display client information. Only the client side NFS, RPC, and
NFS_ACL information is printed. Can be combined with the -n, -r,
and -a options to print client side NFS, RPC, and NFS_ACL
information only.
-m [pathname...]
Display statistics for each NFS mounted file system. If pathname
is not specified, displays statistics for all NFS mounted file
systems. If pathname is specified, displays statistics for the
NFS mounted file systems indicated by pathname.
This includes the server name and address, mount flags, current
read and write sizes, the retransmission count, the attribute
cache timeout values, failover information, and the timers used
for dynamic retransmission. The dynamic retransmission timers are
displayed only where dynamic retransmission is in use. By
default, NFS mounts over the TCP protocols and NFS Version 3
mounts over either TCP or UDP do not use dynamic retransmission.
If you specify the -m option, this is the only option that
nfsstat uses. If you specify other options with -m, you receive
an error message alerting that the -m flag cannot be combined
with other options.
-n
Display NFS information. NFS information for both the client and
server side are printed. Can be combined with the -c and -s
options to print client or server NFS information only.
-r
Display RPC information.
-s
Display server information.
-T u | d
Display a time stamp.
Specify u for a printed representation of the internal
representation of time. See time(2). Specify d for standard date
format. See date(1).
-v version
Specify which NFS version for which to print statistics. When
followed by the optional version argument, (2|3|4), specifies
statistics for that version. By default, prints statistics for
all versions.
-z
Zero (reinitialize) statistics. This option is for use by the
super user only, and can be combined with any of the above
options to zero particular sets of statistics after printing
them.
OPERANDS
The following operands are supported:
count
Display only count reports
interval
Report once each interval seconds.
pathname
Specify the pathname of a file in an NFS mounted file system for
which statistics are to be displayed.
DISPLAYS
The server RPC display includes the following fields:
badcalls
The total number of calls rejected by the RPC layer (the sum of
badlen and xdrcall as defined below).
badlen
The number of RPC calls with a length shorter than a minimum-
sized RPC call.
calls
The total number of RPC calls received.
dupchecks
The number of RPC calls that looked up in the duplicate request
cache.
dupreqs
The number of RPC calls that were found to be duplicates.
nullrecv
The number of times an RPC call was not available when it was
thought to be received.
xdrcall
The number of RPC calls whose header could not be XDR decoded.
The server NFS display shows the number of NFS calls received (calls)
and rejected (badcalls), and the counts and percentages for the
various calls that were made.
The server NFS_ACL display shows the counts and percentages for the
various calls that were made.
The client RPC display includes the following fields:
calls
The total number of RPC calls made.
badcalls
The total number of calls rejected by the RPC layer.
badverfs
The number of times the call failed due to a bad verifier in the
response.
badxids
The number of times a reply from a server was received which did
not correspond to any outstanding call.
cantconn
The number of times the call failed due to a failure to make a
connection to the server.
cantsend
The number of times a client was unable to send an RPC request
over a connectionless transport when it tried to do so.
interrupts
The number of times the call was interrupted by a signal before
completing.
newcreds
The number of times authentication information had to be
refreshed.
nomem
The number of times the call failed due to a failure to allocate
memory.
retrans
The number of times a call had to be retransmitted due to a
timeout while waiting for a reply from the server. Applicable
only to RPC over connection-less transports.
timeouts
The number of times a call timed out while waiting for a reply
from the server.
timers
The number of times the calculated time-out value was greater
than or equal to the minimum specified time-out value for a call.
The client NFS display shows the number of calls sent and rejected,
as well as the number of times a CLIENT handle was received (clgets),
the number of times the CLIENT handle cache had no unused entries
(cltoomany), as well as a count of the various calls and their
respective percentages.
The client NFS_ACL display shows the counts and percentages for the
various calls that were made.
The -m option includes information about mount flags set by mount
options, mount flags internal to the system, and other mount
information. See mount_nfs(8).
The following mount flags are set by mount options:
grpid
System V group id inheritance.
hard
Hard mount.
intr
Interrupts allowed on hard mount.
llock
Local locking being used (no lock manager).
noac
Client is not caching attributes.
nointr
No interrupts allowed on hard mount.
nocto
No close-to-open consistency.
retrans
NFS retransmissions.
rpctimesync
RPC time sync.
rsize
Read buffer size in bytes.
sec
sec has one of the following values:
dh
des-style authentication (encrypted timestamps).
krb5
kerberos v5-style authentication.
krb5i
kerberos v5-style authentication with integrity.
krb5p
kerberos v5-style authentication with privacy.
none
No authentication.
short
Short hand UNIX-style authentication.
sys
UNIX-style authentication (UID, GID).
soft
Soft mount.
timeo
Initial NFS timeout, in tenths of a second.
wsize
Write buffer size in bytes.
The following mount flags are internal to the system:
acl
Server supports NFS_ACL.
down
Server is down.
dynamic
Dynamic transfer size adjustment.
link
Server supports links.
mirrormount
Mounted automatically by means of the mirrormount mechanism.
printed
"Not responding" message printed.
readdir
Use readdir instead of readdirplus.
symlink
Server supports symbolic links.
The following flags relate to additional mount information:
proto
Protocol.
vers
NFS version.
The -m option also provides attribute cache timeout values. The
following fields in -m output provide timeout values for attribute
cache:
acdirmax
Maximum seconds to hold cached directory attributes.
acdirmin
Minimum seconds to hold cached directory attributes.
acregmax
Maximum seconds to hold cached file attributes.
acregmin
Minimum seconds to hold cached file attributes.
The following fields in -m output provide failover information:
currserver
Which server is currently providing NFS service. See the for
additional details.
failover
How many times a new server has been selected.
noresponse
How many times servers have failed to respond.
remap
How many times files have been re-evaluated to the new server.
The fields in -m output shown below provide information on dynamic
retransmissions. These items are displayed only where dynamic
retransmission is in use.
cur
Current backed-off retransmission value, in milliseconds.
dev
Estimated deviation, in milliseconds.
srtt
The value for the smoothed round-trip time, in milliseconds.
EXIT STATUS
The following exit values are returned:
0
Successful completion.
>0
An error occurred.
SEE ALSO
attributes(7), mount_nfs(8)
June 16, 2009 NFSSTAT(8)