Re: [PATCH] rpc_lib.sh: fix portmapper detection in case of socket activation

Re: [PATCH] rpc_lib.sh: fix portmapper detection in case of socket activation

[Petr Vorel]

Hi Nikita,

[ Cc: Steve as user-space maintainer, also Neil and whole linux-nfs ]

> On systemd-based linux hosts, rpcbind service is typically started via
> socket activation, when the first client connects. If no client has
> connected before LTP rpc test starts, rpcbind process will not be
> running at the time of check_portmap_rpcbind() execution, causing
> check_portmap_rpcbind() to report TCONF error.

> Fix that by adding a quiet invocation of 'rpcinfo' before checking for
> rpcbind.

Looks reasonable, but I'd prefer to have confirmation from NFS experts.

> For portmap, similar step is likely not needed, because portmap is used
> only on old systemd and those don't use systemd.

> Signed-off-by: Nikita Yushchenko <nikita.yushchenko@virtuozzo.com>
> ---
>  testcases/network/rpc/basic_tests/rpc_lib.sh | 6 ++++++
>  1 file changed, 6 insertions(+)

> diff --git a/testcases/network/rpc/basic_tests/rpc_lib.sh b/testcases/network/rpc/basic_tests/rpc_lib.sh
> index c7c868709..e882e41b3 100644
> --- a/testcases/network/rpc/basic_tests/rpc_lib.sh
> +++ b/testcases/network/rpc/basic_tests/rpc_lib.sh
> @@ -8,6 +8,12 @@ check_portmap_rpcbind()
>  	if pgrep portmap > /dev/null; then
>  		PORTMAPPER="portmap"
>  	else
> +		# In case of systemd socket activation, rpcbind could be
> +		# not started until somebody tries to connect to it's socket.
> +		#
> +		# To handle that case properly, run a client now.
> +		rpcinfo >/dev/null 2>&1
nit: Shouldn't we keep stderr? In LTP we put required commands into
$TST_NEEDS_CMDS. It'd be better not require rpcinfo (not a hard dependency),
and thus it'd be better to see "command not found" when rpcinfo missing and test
fails.

Kind regards,
Petr

> +
>  		pgrep rpcbind > /dev/null && PORTMAPPER="rpcbind" || \
>  			tst_brk TCONF "portmap or rpcbind is not running"
>  	fi

Re: [PATCH] rpc_lib.sh: fix portmapper detection in case of socket activation

[Nikita Yushchenko]

21.01.2022 00:01, Petr Vorel wrote:
> Hi Nikita,
> 
> [ Cc: Steve as user-space maintainer, also Neil and whole linux-nfs ]
> 
>> On systemd-based linux hosts, rpcbind service is typically started via
>> socket activation, when the first client connects. If no client has
>> connected before LTP rpc test starts, rpcbind process will not be
>> running at the time of check_portmap_rpcbind() execution, causing
>> check_portmap_rpcbind() to report TCONF error.
> 
>> Fix that by adding a quiet invocation of 'rpcinfo' before checking for
>> rpcbind.
> 
> Looks reasonable, but I'd prefer to have confirmation from NFS experts.

NFS is not involved here, this is about sunrpc tests.

I had to add this patch to make 'runltp -f net.rpc' pass just after container is started - that happens 
in container autotests here.

Nikita

Re: [PATCH] rpc_lib.sh: fix portmapper detection in case of socket activation

[Petr Vorel]

Hi Nikita,

> 21.01.2022 00:01, Petr Vorel wrote:
> > Hi Nikita,

> > [ Cc: Steve as user-space maintainer, also Neil and whole linux-nfs ]

> > > On systemd-based linux hosts, rpcbind service is typically started via
> > > socket activation, when the first client connects. If no client has
> > > connected before LTP rpc test starts, rpcbind process will not be
> > > running at the time of check_portmap_rpcbind() execution, causing
> > > check_portmap_rpcbind() to report TCONF error.

> > > Fix that by adding a quiet invocation of 'rpcinfo' before checking for
> > > rpcbind.

> > Looks reasonable, but I'd prefer to have confirmation from NFS experts.

> NFS is not involved here, this is about sunrpc tests.
Sure. Just tirpc (in libtirpc or the the old SUN-RPC already removed from glibc)
are used in NFS. Steve is the libtirpc maintainer.

> I had to add this patch to make 'runltp -f net.rpc' pass just after
> container is started - that happens in container autotests here.
Yep, I suspected this. Because on normal linux distro it's working right after
boot (tested on rpc01.sh). Can't this be a setup issue?

Kind regards,
Petr

> Nikita

Re: [PATCH] rpc_lib.sh: fix portmapper detection in case of socket activation

[Nikita Yushchenko]

> 
>> I had to add this patch to make 'runltp -f net.rpc' pass just after
>> container is started - that happens in container autotests here.
> Yep, I suspected this. Because on normal linux distro it's working right after
> boot (tested on rpc01.sh). Can't this be a setup issue?

This depends on what is installed and how it is configured.

But definitely the state with rpcbind process not running and systemd is listening on rpcbind sockets - 
is valid.

In the setup where the issue was caught, the test harness creates a container with minimal centos8 setup 
inside, boots it, and starts ltp inside.

Just reproduced manually:

[root@vz8 ~]# vzctl start 1000
Starting Container ...
...
[root@vz8 ~]# vzctl enter 1000
entered into CT 1000
CT-1000 /# pidof rpcbind
CT-1000 /# rpcinfo > /dev/null 2>&1
CT-1000 /# pidof rpcbind
678
CT-1000 /#

Re: [PATCH] rpc_lib.sh: fix portmapper detection in case of socket activation

[Petr Vorel]

> > > I had to add this patch to make 'runltp -f net.rpc' pass just after
> > > container is started - that happens in container autotests here.
> > Yep, I suspected this. Because on normal linux distro it's working right after
> > boot (tested on rpc01.sh). Can't this be a setup issue?

> This depends on what is installed and how it is configured.

> But definitely the state with rpcbind process not running and systemd is
> listening on rpcbind sockets - is valid.

> In the setup where the issue was caught, the test harness creates a
> container with minimal centos8 setup inside, boots it, and starts ltp
> inside.

> Just reproduced manually:

> [root@vz8 ~]# vzctl start 1000
> Starting Container ...
> ...
> [root@vz8 ~]# vzctl enter 1000
> entered into CT 1000
> CT-1000 /# pidof rpcbind
> CT-1000 /# rpcinfo > /dev/null 2>&1
> CT-1000 /# pidof rpcbind
> 678
> CT-1000 /#

Thanks for info. I'm asking because if it's a setup bug it should not be hidden
by workaround but reported. I suppose normal Centos8 VM works.

Kind regards,
Petr

Re: [PATCH] rpc_lib.sh: fix portmapper detection in case of socket activation

[Nikita Yushchenko]

>> Just reproduced manually:
> 
>> [root@vz8 ~]# vzctl start 1000
>> Starting Container ...
>> ...
>> [root@vz8 ~]# vzctl enter 1000
>> entered into CT 1000
>> CT-1000 /# pidof rpcbind
>> CT-1000 /# rpcinfo > /dev/null 2>&1
>> CT-1000 /# pidof rpcbind
>> 678
>> CT-1000 /#
> 
> Thanks for info. I'm asking because if it's a setup bug it should not be hidden
> by workaround but reported. I suppose normal Centos8 VM works.

I's say this is starting service on demand and this is exactly what socket activation is designed for.

Re: [PATCH] rpc_lib.sh: fix portmapper detection in case of socket activation

[NeilBrown]

On Fri, 21 Jan 2022, Petr Vorel wrote:
> Hi Nikita,
> 
> [ Cc: Steve as user-space maintainer, also Neil and whole linux-nfs ]
> 
> > On systemd-based linux hosts, rpcbind service is typically started via
> > socket activation, when the first client connects. If no client has
> > connected before LTP rpc test starts, rpcbind process will not be
> > running at the time of check_portmap_rpcbind() execution, causing
> > check_portmap_rpcbind() to report TCONF error.
> 
> > Fix that by adding a quiet invocation of 'rpcinfo' before checking for
> > rpcbind.
> 
> Looks reasonable, but I'd prefer to have confirmation from NFS experts.
> 
> > For portmap, similar step is likely not needed, because portmap is used
> > only on old systemd and those don't use systemd.
> 
> > Signed-off-by: Nikita Yushchenko <nikita.yushchenko@virtuozzo.com>
> > ---
> >  testcases/network/rpc/basic_tests/rpc_lib.sh | 6 ++++++
> >  1 file changed, 6 insertions(+)
> 
> > diff --git a/testcases/network/rpc/basic_tests/rpc_lib.sh b/testcases/network/rpc/basic_tests/rpc_lib.sh
> > index c7c868709..e882e41b3 100644
> > --- a/testcases/network/rpc/basic_tests/rpc_lib.sh
> > +++ b/testcases/network/rpc/basic_tests/rpc_lib.sh
> > @@ -8,6 +8,12 @@ check_portmap_rpcbind()
> >  	if pgrep portmap > /dev/null; then
> >  		PORTMAPPER="portmap"
> >  	else
> > +		# In case of systemd socket activation, rpcbind could be
> > +		# not started until somebody tries to connect to it's socket.
> > +		#
> > +		# To handle that case properly, run a client now.
> > +		rpcinfo >/dev/null 2>&1

If it were me, I would remove the 'pgrep's and just call "rpcbind -p"
and make sure something responds.

NeilBrown



> nit: Shouldn't we keep stderr? In LTP we put required commands into
> $TST_NEEDS_CMDS. It'd be better not require rpcinfo (not a hard dependency),
> and thus it'd be better to see "command not found" when rpcinfo missing and test
> fails.
> 
> Kind regards,
> Petr
> 
> > +
> >  		pgrep rpcbind > /dev/null && PORTMAPPER="rpcbind" || \
> >  			tst_brk TCONF "portmap or rpcbind is not running"
> >  	fi
> 
> 

Re: [PATCH] rpc_lib.sh: fix portmapper detection in case of socket activation

[Petr Vorel]

> On Fri, 21 Jan 2022, Petr Vorel wrote:
> > Hi Nikita,

> > [ Cc: Steve as user-space maintainer, also Neil and whole linux-nfs ]

> > > On systemd-based linux hosts, rpcbind service is typically started via
> > > socket activation, when the first client connects. If no client has
> > > connected before LTP rpc test starts, rpcbind process will not be
> > > running at the time of check_portmap_rpcbind() execution, causing
> > > check_portmap_rpcbind() to report TCONF error.

> > > Fix that by adding a quiet invocation of 'rpcinfo' before checking for
> > > rpcbind.

> > Looks reasonable, but I'd prefer to have confirmation from NFS experts.

> > > For portmap, similar step is likely not needed, because portmap is used
> > > only on old systemd and those don't use systemd.

> > > Signed-off-by: Nikita Yushchenko <nikita.yushchenko@virtuozzo.com>
> > > ---
> > >  testcases/network/rpc/basic_tests/rpc_lib.sh | 6 ++++++
> > >  1 file changed, 6 insertions(+)

> > > diff --git a/testcases/network/rpc/basic_tests/rpc_lib.sh b/testcases/network/rpc/basic_tests/rpc_lib.sh
> > > index c7c868709..e882e41b3 100644
> > > --- a/testcases/network/rpc/basic_tests/rpc_lib.sh
> > > +++ b/testcases/network/rpc/basic_tests/rpc_lib.sh
> > > @@ -8,6 +8,12 @@ check_portmap_rpcbind()
> > >  	if pgrep portmap > /dev/null; then
> > >  		PORTMAPPER="portmap"
> > >  	else
> > > +		# In case of systemd socket activation, rpcbind could be
> > > +		# not started until somebody tries to connect to it's socket.
> > > +		#
> > > +		# To handle that case properly, run a client now.
> > > +		rpcinfo >/dev/null 2>&1

> If it were me, I would remove the 'pgrep's and just call "rpcbind -p"
> and make sure something responds.

Hi Neil,

I guess you mean: rpcinfo -p

Good idea, thanks!

Kind regards,
Petr

> NeilBrown



> > nit: Shouldn't we keep stderr? In LTP we put required commands into
> > $TST_NEEDS_CMDS. It'd be better not require rpcinfo (not a hard dependency),
> > and thus it'd be better to see "command not found" when rpcinfo missing and test
> > fails.

> > Kind regards,
> > Petr

> > > +
> > >  		pgrep rpcbind > /dev/null && PORTMAPPER="rpcbind" || \
> > >  			tst_brk TCONF "portmap or rpcbind is not running"
> > >  	fi