# Network Filesystem Input Plugin This plugin collects metrics about operations on [Network Filesystem][nfs] mounts. By default, only a limited number of general system-level metrics are collected, including basic read/write counts but more detailed metrics can be enabled. > [!NOTE] > Many of the metrics, even if tagged with a mount point, are really > _per-server_. E.g. if you mount two shares: `nfs01:/vol/foo/bar` and > `nfs01:/vol/foo/baz`, there will be two near identical entries in > `/proc/self/mountstats`. This is a limitation of the metrics exposed by the > kernel, not by this plugin. ⭐ Telegraf v1.18.0 🏷️ network, system 💻 all [nfs]: https://www.ietf.org/rfc/rfc1813.txt?number=1813 ## Global configuration options Plugins support additional global and plugin configuration settings for tasks such as modifying metrics, tags, and fields, creating aliases, and configuring plugin ordering. See [CONFIGURATION.md][CONFIGURATION.md] for more details. [CONFIGURATION.md]: ../../../docs/CONFIGURATION.md#plugins ## Configuration ```toml @sample.conf # Read per-mount NFS client metrics from /proc/self/mountstats [[inputs.nfsclient]] ## Read more low-level metrics (optional, defaults to false) # fullstat = false ## List of mounts to explicitly include or exclude (optional) ## The pattern (Go regexp) is matched against the mount point (not the ## device being mounted). If include_mounts is set, all mounts are ignored ## unless present in the list. If a mount is listed in both include_mounts ## and exclude_mounts, it is excluded. Go regexp patterns can be used. # include_mounts = [] # exclude_mounts = [] ## List of operations to include or exclude from collecting. This applies ## only when fullstat=true. Semantics are similar to {include,exclude}_mounts: ## the default is to collect everything; when include_operations is set, only ## those OPs are collected; when exclude_operations is set, all are collected ## except those listed. If include and exclude are set, the OP is excluded. ## See /proc/self/mountstats for a list of valid operations; note that ## NFSv3 and NFSv4 have different lists. While it is not possible to ## have different include/exclude lists for NFSv3/4, unused elements ## in the list should be okay. It is possible to have different lists ## for different mountpoints: use multiple [[input.nfsclient]] stanzas, ## with their own lists. See "include_mounts" above, and be careful of ## duplicate metrics. # include_operations = [] # exclude_operations = [] ``` ### Configuration Options - `fullstat`: Collect per-operation type metrics. Defaults to false. - `include_mounts`: gather metrics for only these mounts. Default is to watch all mounts. - `exclude_mounts`: gather metrics for all mounts, except those listed in this option. Excludes take precedence over includes. - `include_operations`: List of specific NFS operations to track. See `/proc/self/mountstats` (the "per-op statistics" section) for a complete lists of valid options for NFSv3 and NFSV4. The default is to gather all metrics, but this is almost certainly _not_ what you want (there are 22 operations for NFSv3, and well over 50 for NFSv4). A suggested 'minimal' list of operations to collect for basic usage: `['READ','WRITE','ACCESS','GETATTR','READDIR','LOOKUP','LOOKUP']` - `exclude_operations`: Gather all metrics, except those listed. Excludes take precedence over includes. > [!NOTE] > The `include_mounts` and `exclude_mounts` arguments are both applied to the > local mount location (e.g. /mnt/NFS), not the server export (e.g. > nfsserver:/vol/NFS). Go regexp patterns can be used in either. ## Location of mountstats If you have mounted the `/proc` file system in a container, to tell this plugin where to find the new location, set the `MOUNT_PROC` environment variable. For example, in a Docker compose file, if `/proc` is mounted to `/host/proc`, then use: ```yaml MOUNT_PROC: /host/proc/self/mountstats ``` ## Metrics Fields: - nfsstat - bytes (integer, bytes) - The total number of bytes exchanged doing this operation. This is bytes sent _and_ received, including overhead _and_ payload (`bytes = OP_bytes_sent + OP_bytes_recv`). See `nfs_ops` below. - ops (integer, count) - The number of operations of this type executed. - retrans (integer, count) - The number of times an operation had to be (`retried retrans = OP_trans - OP_ops`). See `nfs_ops` below. - exe (integer, milliseconds) - The number of milliseconds it took to process the operations. - rtt (integer, milliseconds) - The total round-trip time for all operations. - rtt_per_op (float, milliseconds) - The average round-trip time per operation. In addition enabling `fullstat` will make many more metrics available. Tags: - All measurements have the following tags: - mountpoint - The local mountpoint, for instance: "/var/www" - serverexport - The full server export, for instance: "nfsserver.example.org:/export" - Measurements nfsstat and nfs_ops will also include: - operation - the NFS operation in question. `READ` or `WRITE` for nfsstat, but potentially one of ~20 or ~50, depending on NFS version. A complete list of operations supported is visible in `/proc/self/mountstats`. ### Additional metrics When `fullstat` is true, additional measurements are collected. Tags are the same as above. NFS Operations: Most descriptions come from [Reference][ref] and `nfs_iostat.h`. Field order and names are the same as in `/proc/self/mountstats` and the Kernel source. Please refer to `/proc/self/mountstats` for a list of supported NFS operations, as it changes occasionally. - nfs_bytes - fields: - normalreadbytes (int, bytes): Bytes read from the server via `read()` - normalwritebytes (int, bytes): Bytes written to the server via `write()` - directreadbytes (int, bytes): Bytes read with O_DIRECT set - directwritebytes (int, bytes): Bytes written with O_DIRECT set - serverreadbytes (int, bytes): Bytes read via NFS READ (via `mmap()`) - serverwritebytes (int, bytes): Bytes written via NFS WRITE (via `mmap()`) - readpages (int, count): Number of pages read - writepages (int, count): Number of pages written - nfs_events (Per-event metrics) - fields: - inoderevalidates (int, count): How many times cached inode attributes have to be re-validated from the server. - dentryrevalidates (int, count): How many times cached dentry nodes have to be re-validated. - datainvalidates (int, count): How many times an inode had its cached data thrown out. - attrinvalidates (int, count): How many times an inode has had cached inode attributes invalidated. - vfsopen (int, count): How many times files or directories have been `open()`'d. - vfslookup (int, count): How many name lookups in directories there have been. - vfsaccess (int, count): Number of calls to `access()`. (formerly called "vfspermission") - vfsupdatepage (int, count): Count of updates (and potential writes) to pages. - vfsreadpage (int, count): Number of pages read. - vfsreadpages (int, count): Count of how many times a _group_ of pages was read (possibly via `mmap()`?). - vfswritepage (int, count): Number of pages written. - vfswritepages (int, count): Count of how many times a _group_ of pages was written (possibly via `mmap()`?) - vfsgetdents (int, count): Count of directory entry reads with getdents(). These reads can be served from cache and don't necessarily imply actual NFS requests. (formerly called "vfsreaddir") - vfssetattr (int, count): How many times we've set attributes on inodes. - vfsflush (int, count): Count of times pending writes have been forcibly flushed to the server. - vfsfsync (int, count): Count of calls to `fsync()` on directories and files. - vfslock (int, count): Number of times a lock was attempted on a file (regardless of success or not). - vfsrelease (int, count): Number of calls to `close()`. - congestionwait (int, count): Believe unused by the Linux kernel, but it is part of the NFS spec. - setattrtrunc (int, count): How many times files have had their size truncated. - extendwrite (int, count): How many times a file has been grown because you're writing beyond the existing end of the file. - sillyrenames (int, count): Number of times an in-use file was removed (thus creating a temporary ".nfsXXXXXX" file) - shortreads (int, count): Number of times the NFS server returned less data than requested. - shortwrites (int, count): Number of times NFS server reports it wrote less data than requested. - delay (int, count): Occurrences of EJUKEBOX ("Jukebox Delay", probably unused) - pnfsreads (int, count): Count of NFS v4.1+ pNFS reads. - pnfswrites (int, count): Count of NFS v4.1+ pNFS writes. - nfs_xprt_tcp - fields: - bind_count (int, count): Number of_completely new_ mounts to this server (sometimes 0?) - connect_count (int, count): How many times the client has connected to the server in question - connect_time (int, jiffies): How long the NFS client has spent waiting for its connection(s) to the server to be established. - idle_time (int, seconds): How long (in seconds) since the NFS mount saw any RPC traffic. - rpcsends (int, count): How many RPC requests this mount has sent to the server. - rpcreceives (int, count): How many RPC replies this mount has received from the server. - badxids (int, count): Count of XIDs sent by the server that the client doesn't know about. - inflightsends (int, count): Number of outstanding requests; always >1. (See reference #4 for comment on this field) - backlogutil (int, count): Cumulative backlog count - nfs_xprt_udp - fields: - [same as nfs_xprt_tcp, except for connect_count, connect_time, and idle_time] - nfs_ops - fields with the `operations` tag being set to the uppercase name of the NFS operation in all cases , _e.g._ "READ", "FSINFO", _etc_. See `/proc/self/mountstats` for a full list: - ops (int, count): Total operations of this type. - trans (int, count): Total transmissions of this type, including retransmissions (lower is better): `OP_ops - OP_trans = total_retransmissions`. - timeouts (int, count): Number of major timeouts. - bytes_sent (int, count): Bytes sent, including headers (should also be close to on-wire size). - bytes_recv (int, count): Bytes received, including headers (should be close to on-wire size). - queue_time (int, milliseconds): Cumulative time a request waited in the queue before sending this OP type. - response_time (int, milliseconds): Cumulative time waiting for a response for this OP type. - total_time (int, milliseconds): Cumulative time a request waited in the queue before sending. - errors (int, count): Total number operations that complete with tk_status < 0 (usually errors). This is a new field, present in kernel >=5.3, mountstats version 1.1 [ref]: https://utcc.utoronto.ca/~cks/space/blog/linux/NFSMountstatsIndex ## Example Output For basic metrics showing server-wise read and write data. ```text nfsstat,mountpoint=/NFS,operation=READ,serverexport=1.2.3.4:/storage/NFS ops=600i,retrans=1i,bytes=1207i,rtt=606i,exe=607i 1612651512000000000 nfsstat,mountpoint=/NFS,operation=WRITE,serverexport=1.2.3.4:/storage/NFS bytes=1407i,rtt=706i,exe=707i,ops=700i,retrans=1i 1612651512000000000 ``` For `fullstat=true` metrics, which includes additional measurements for `nfs_bytes`, `nfs_events`, and `nfs_xprt_tcp` (and `nfs_xprt_udp` if present). Additionally, per-OP metrics are collected, with examples for READ, LOOKUP, and NULL shown. Please refer to `/proc/self/mountstats` for a list of supported NFS operations, as it changes as it changes periodically. ```text nfs_bytes,mountpoint=/home,serverexport=nfs01:/vol/home directreadbytes=0i,directwritebytes=0i,normalreadbytes=42648757667i,normalwritebytes=0i,readpages=10404603i,serverreadbytes=42617098139i,serverwritebytes=0i,writepages=0i 1608787697000000000 nfs_events,mountpoint=/home,serverexport=nfs01:/vol/home attrinvalidates=116i,congestionwait=0i,datainvalidates=65i,delay=0i,dentryrevalidates=5911243i,extendwrite=0i,inoderevalidates=200378i,pnfsreads=0i,pnfswrites=0i,setattrtrunc=0i,shortreads=0i,shortwrites=0i,sillyrenames=0i,vfsaccess=7203852i,vfsflush=117405i,vfsfsync=0i,vfsgetdents=3368i,vfslock=0i,vfslookup=740i,vfsopen=157281i,vfsreadpage=16i,vfsreadpages=86874i,vfsrelease=155526i,vfssetattr=0i,vfsupdatepage=0i,vfswritepage=0i,vfswritepages=215514i 1608787697000000000 nfs_xprt_tcp,mountpoint=/home,serverexport=nfs01:/vol/home backlogutil=0i,badxids=0i,bind_count=1i,connect_count=1i,connect_time=0i,idle_time=0i,inflightsends=15659826i,rpcreceives=2173896i,rpcsends=2173896i 1608787697000000000 nfs_ops,mountpoint=/NFS,operation=NULL,serverexport=1.2.3.4:/storage/NFS trans=0i,timeouts=0i,bytes_sent=0i,bytes_recv=0i,queue_time=0i,response_time=0i,total_time=0i,ops=0i 1612651512000000000 nfs_ops,mountpoint=/NFS,operation=READ,serverexport=1.2.3.4:/storage/NFS bytes=1207i,timeouts=602i,total_time=607i,exe=607i,trans=601i,bytes_sent=603i,bytes_recv=604i,queue_time=605i,ops=600i,retrans=1i,rtt=606i,response_time=606i 1612651512000000000 nfs_ops,mountpoint=/NFS,operation=WRITE,serverexport=1.2.3.4:/storage/NFS ops=700i,bytes=1407i,exe=707i,trans=701i,timeouts=702i,response_time=706i,total_time=707i,retrans=1i,rtt=706i,bytes_sent=703i,bytes_recv=704i,queue_time=705i 1612651512000000000 ```