| Message ID | 20210111214143.553479-1-Anna.Schumaker@Netapp.com (mailing list archive) |
|---|---|
| Headers | show |
| Series | SUNRPC: Create sysfs files for changing IP | expand |
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? > 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
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 > >
On Tue, Jan 12, 2021 at 11:59 AM J. Bruce Fields <bfields@fieldses.org> wrote: > > 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 ? Possibly! I was trying to match /sys/fs/nfs, but I can definitely change this if another location is better. > > > > 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? Yeah, I would expect there to be a new utility to help with assigning new values. I haven't given any thought to using fs_locations yet, but it could probably work. > > 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? The mount call doesn't give us a host name (that I can find, at least). By the time we get to the sunrpc layer we're dealing with just the IP address anyway. I'd expect there to be a userland utility to translate the dns name to the new IP address and pass it along to the new API. Anna > > --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 > > > >
> On Jan 13, 2021, at 2:23 PM, Anna Schumaker <schumaker.anna@gmail.com> wrote: > > On Tue, Jan 12, 2021 at 11:59 AM J. Bruce Fields <bfields@fieldses.org> wrote: >> >> 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 ? > > Possibly! I was trying to match /sys/fs/nfs, but I can definitely > change this if another location is better. Ah... since this is a supplement to the mount() interface, maybe placing this new API under /sys/fs/nfs/ might make some sense. >>> 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? > > Yeah, I would expect there to be a new utility to help with assigning > new values. I haven't given any thought to using fs_locations yet, but > it could probably work. I could see a tool that performs an fs_locations from user space and plugs that information into the kernel NFS client as needed. Future work! -- Chuck Lever
> On Jan 13, 2021, at 2:48 PM, Chuck Lever <chuck.lever@oracle.com> wrote: > >> On Jan 13, 2021, at 2:23 PM, Anna Schumaker <schumaker.anna@gmail.com> wrote: >> >> On Tue, Jan 12, 2021 at 11:59 AM J. Bruce Fields <bfields@fieldses.org> wrote: >>> >>> 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 ? >> >> Possibly! I was trying to match /sys/fs/nfs, but I can definitely >> change this if another location is better. > > Ah... since this is a supplement to the mount() interface, maybe > placing this new API under /sys/fs/nfs/ might make some sense. Or you could implement it with "-o remount,addr=new-address". -- Chuck Lever
On Wed, Jan 13, 2021 at 9:18 PM Chuck Lever <chuck.lever@oracle.com> wrote: > > > > On Jan 13, 2021, at 2:48 PM, Chuck Lever <chuck.lever@oracle.com> wrote: > > > >> On Jan 13, 2021, at 2:23 PM, Anna Schumaker <schumaker.anna@gmail.com> wrote: > >> > >> On Tue, Jan 12, 2021 at 11:59 AM J. Bruce Fields <bfields@fieldses.org> wrote: > >>> > >>> 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 ? > >> > >> Possibly! I was trying to match /sys/fs/nfs, but I can definitely > >> change this if another location is better. > > > > Ah... since this is a supplement to the mount() interface, maybe > > placing this new API under /sys/fs/nfs/ might make some sense. > > Or you could implement it with "-o remount,addr=new-address". A change of address is currently not allowed by the NFS because multiple mounts might be sharing a superblock and change of one mount's option would not be correct. The way things work from this new mechanism is system wide and all mounts are affected. > > > -- > Chuck Lever > > >
> On Jan 14, 2021, at 3:29 PM, Olga Kornievskaia <aglo@umich.edu> wrote: > > On Wed, Jan 13, 2021 at 9:18 PM Chuck Lever <chuck.lever@oracle.com> wrote: >> >> >>> On Jan 13, 2021, at 2:48 PM, Chuck Lever <chuck.lever@oracle.com> wrote: >>> >>>> On Jan 13, 2021, at 2:23 PM, Anna Schumaker <schumaker.anna@gmail.com> wrote: >>>> >>>> On Tue, Jan 12, 2021 at 11:59 AM J. Bruce Fields <bfields@fieldses.org> wrote: >>>>> >>>>> 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 ? >>>> >>>> Possibly! I was trying to match /sys/fs/nfs, but I can definitely >>>> change this if another location is better. >>> >>> Ah... since this is a supplement to the mount() interface, maybe >>> placing this new API under /sys/fs/nfs/ might make some sense. >> >> Or you could implement it with "-o remount,addr=new-address". > > A change of address is currently not allowed by the NFS because > multiple mounts might be sharing a superblock and change of one > mount's option would not be correct. The way things work from this new > mechanism is system wide and all mounts are affected. OK, well, if we're going with an API based on /sys that shows underlying transport connections, is there a way to expose whether the connection is established or closed? Maybe also last traffic or last connect attempt? Can it support RPC/RDMA connections too? -- Chuck Lever
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! 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