Re: [RFC PATCH 0/7] SUNRPC: Create sysfs files for changing IP

J. Bruce Fields
2021-01-12T17:00:12Z

On Tue, Jan 12, 2021 at 08:09:09AM -0500, Chuck Lever wrote:
> Hi Anna-
>
> > On Jan 11, 2021, at 4:41 PM, schumaker.anna@gmail.com wrote:
> >
> > From: Anna Schumaker <Anna.Schumaker@Netapp.com>
> >
> > It's possible for an NFS server to go down but come back up with a
> > different IP address. These patches provide a way for administrators to
> > handle this issue by providing a new IP address for xprt sockets to
> > connect to.
> >
> > This is a first draft of the code, so any thoughts or suggestions would
> > be greatly appreciated!
>
> One implementation question, one future question.
>
> Would /sys/kernel/net be a little better? or /sys/kernel/sunrpc ?
>
> Do you have a plan to integrate support for fs_locations to probe
> servers for alternate IP addresses? Would that be a userspace
> utility that would plug values into this new /sys API?

We already have dns resolution for fs_locations, right? Why can't we
use that here? Is it that the mount call doesn't give us a host name?
Or we don't trust dns to have the updated IP address for some reason?

--b.

>
>
> > Anna
> >
> >
> > Anna Schumaker (7):
> > net: Add a /sys/net directory to sysfs
> > sunrpc: Create a sunrpc directory under /sys/net/
> > sunrpc: Create a net/ subdirectory in the sunrpc sysfs
> > sunrpc: Create per-rpc_clnt sysfs kobjects
> > sunrpc: Create a per-rpc_clnt file for managing the IP address
> > sunrpc: Prepare xs_connect() for taking NULL tasks
> > sunrpc: Connect to a new IP address provided by the user
> >
> > include/linux/sunrpc/clnt.h | 1 +
> > include/net/sock.h | 4 +
> > net/socket.c | 8 ++
> > net/sunrpc/Makefile | 2 +-
> > net/sunrpc/clnt.c | 5 ++
> > net/sunrpc/sunrpc_syms.c | 8 ++
> > net/sunrpc/sysfs.c | 160 ++++++++++++++++++++++++++++++++++++
> > net/sunrpc/sysfs.h | 22 +++++
> > net/sunrpc/xprtsock.c | 3 +-
> > 9 files changed, 211 insertions(+), 2 deletions(-)
> > create mode 100644 net/sunrpc/sysfs.c
> > create mode 100644 net/sunrpc/sysfs.h
> >
> > --
> > 2.29.2
> >
>
> --
> Chuck Lever
>
>