Mount and transport state
Normally, the mountstats
command shows NFS mount status. We have extended the
interface it uses, /proc/self/mountstats
, with our own extra state reporting
via /sys
. The extended information contains the IP addresses related to the
transport, and a string that indicates its state flags.
The extended form of it is obtainable via /sys/kernel/debug
. For the
association to an NFS mount, we need to obtain the related sunrpc-id
of the
mount point.
But first, we need to enable sunrpc-id
reporting. This can be done using
the following command after boot:
echo 1 | sudo tee /sys/module/sunrpc/parameters/expose_id_in_mountstats
Then, identify the sunrpc-id
relevant to the mount point by looking into
/proc/self/mountstats
:
$ cat /proc/self/mountstats | grep -E 'fstype nfs|sunrpc-id'
device 192.168.40.7:/opt/export mounted on /mnt/export with fstype nfs statvers=1.1
sunrpc-id: 4
Now we are ready to fetch the full mountstats
via the following command:
sudo cat /sys/kernel/debug/sunrpc/rpc_clnt/4/stats
The added information contains multipath IP address information per xprt
(transport) and xprt
state in string format. The numbers in the first xprt:
line are counters and other numbers related that transports.
For example:
xprt: rdma 0 0 1 0 24 3 3 0 3 0 0 0 0 0 0 0 0 0 0 0 0 0 0 11 0 0 0
172.25.1.101 -> 172.25.1.1, state: CONNECTED BOUND
xprt: rdma 0 0 1 0 24 1 1 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 11 0 0 0
172.25.1.102 -> 172.25.1.2, state: CONNECTED BOUND
xprt: rdma 0 0 1 0 23 1 1 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 11 0 0 0
172.25.1.103 -> 172.25.1.3, state: CONNECTED BOUND
xprt: rdma 0 0 1 0 22 1 1 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 11 0 0 0
172.25.1.104 -> 172.25.1.4, state: CONNECTED BOUND
xprt: rdma 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
172.25.1.101 -> 172.25.1.5, state: BOUND
xprt: rdma 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
172.25.1.102 -> 172.25.1.6, state: BOUND
xprt: rdma 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
172.25.1.103 -> 172.25.1.7, state: BOUND
xprt: rdma 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
172.25.1.104 -> 172.25.1.8, state: BOUND
Document generated on 2025.06.13 19:31 for v4.0.34, branch 4.0