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Hi Tommaso,

Comments interspersed....

On Fri, 28 Aug 2015, Tommaso Boccali wrote:

> ciao,
> the supervisor (started by hand with
> 'cmsd -d -l /var/log/xrootd/superv.log -c
> /etc/xrootd/xrootd-redir-cms-superv.cfg  -k 7' and
> 'xrootd -d -l /var/log/xrootd/superv-x.log -c
> /etc/xrootd/xrootd-redir-cms-superv.cfg -k 7' )
>
The above may be fine except that if you are running a supervisor on the 
same node as the managerr then you really need to differentiate it using 
an instance name. You do this using the '-n' option (e.g. '-n sup1') 
otherwise the two daemons will stomp on each other which is not good. 
Instance names are described in:

http://xrootd.org/doc/dev42/xrd_config.htm#_Toc411375787

Yes, you need to start an xrootd/cmsd pair.

> while in the supervisor cmsd  log I see
> which seems good, but then a series of:
>
> ...
> 150828 14:08:54 28799 manager.0:25@xrootd do_StateFWD: *Path find failed
> for state*
> /store/test/xrootd/T2_MY_UPM_BIRUNI/store/mc/HC/GenericTTbar/GEN-SIM-RECO/CMSSW_7_0_4_START70_V7-v1/00000/D00E55FF-F6CC-E311-9B51-02163E00E88E.root
> 150828 14:08:54 28799 Dispatch manager.0:25@xrootd for state dlen=148
> 150828 14:08:54 28799 manager.0:25@xrootd do_State:
> ...
Well, this is why I recommend not turning on debugging. This is output 
from debugging and the log will be flooded with these kinds of messages 
(usually leading to a logfile that is several gigabytes long). All it 
means is that the manager asked the supervisor to lookup a file but there 
were no subscribers to the supervisor so the lookup could not occur. Quite 
normal.

> So I have a few questions
>
> 0 - very naive: for the supervisor do I need to start cmsd AND xrootd? If I
> do not do that, I see no effect at all
Yes, you need to start a suprevisor xrotd/cmsd pair.

> 1 - is the erorr expected with my config ?
Yes, because full debugging is turned on (I would not recommend that).

> 2 - I did not set explicitly the port numbers to the supervisor, and they
> of course cannot be 1094/1213 since they are already taken by the manager.
> I just have
> xrd.port any
>
> is that enough?
Yes, in fact the supervisor forces arbitrary port number assignment. There 
is no need to give supervisors a specific port.

> 3 - should I see some servers being "moved" by the manager to the
> supervisor?
No, the only time a supervisor is used is when the 65th connection is made 
to the manager. In that case, the connectee is told to connect to the 
supervisor.

> 4 - atm I have not opened any additional port on the firewall, since with
> 'any' I do not know which port will be used. Should I open something?
Well, then we may have a problem here. What is exactly firewalled here? 
That is where do you restrict port number usage?

As for teh config:

>
> [root@xrootd xrootd]# cat /etc/xrootd/xrootd-redir-cms-superv.cfg
>
> xrd.port any
> all.role supervisor
> # The known managers
> all.manager xrootd.ba.infn.it 1213
>
> # Allow any path to be exported; this is further refined in the authfile.
!!! Note that this causes problems for the xrdmapc command and isn't fixed
     until 4.2.3 (Marian has the details). 
> all.export / r/w
>
> # Hosts allowed to use this xrootd cluster
> cms.allow host *
> # Logging verbosity
> xrootd.trace emsg login stall redirect
!!!Unless there is a reason to turn on complete debugging, I strongly 
advise against it as it produces a humongous amount of log output, most of 
which is useless in the general case.

> ofs.trace all -debug
> xrd.trace all -debug
> cms.trace all -debug
>
>
>
> On Thu, Aug 27, 2015 at 5:26 PM, Marian Zvada <[log in to unmask]> wrote:
>
>> Hi Tom,
>>
>> I haven't tried it though, but looks good to me.
>>
>> One more thing, we should not use thread limit by hard from whatever
>> v4.x.x version, I think. This is well cared of within recent fixes I
>> believe. I don't recall details right now but can search through if needed.
>>
>> So, feel free remove the line "xrd.sched maxt 16000".
>>
>> -Marian
>>
>> On 8/27/15 3:49 AM, Tommaso Boccali wrote:
>>
>>> Ciao, I am trying to see if there is the need for a supervisor on one of
>>> our CMS EU redirs.
>>> In the logs, I never really see anything like 'If you suspect this,
>>> check the manager˙˙s log. It will contain warnings about orphaned data
>>> servers'
>>>
>>> so I am not sure we have a problem, but still we a re very close to the
>>> 64 limit so better to be proactive.
>>>
>>>
>>> What I want to do as step #1 is to run the supervisor as an additional
>>> daemon on the redirector (it is a test, I really want to see what
>>> happens first, and the machine is big so should not be an issue)
>>>
>>> I looked at the documentation below, but I have to admit it is a bit
>>> obscure (to me).
>>>
>>> So, I have a cmsd/xrootd (the eu redir) running on ports 1213/1094, and
>>> redirecting "up" if needed (to the global redirector).
>>> Starting from their config, I just wanted to prepare a config for the
>>> supervisor.
>>>
>>> The minimal one I am trying to guess from the documentation would be
>>> ===
>>> xrd.port any
>>> all.role supervisor
>>> # The known managers
>>> all.manager xrootd.ba.infn.it <http://xrootd.ba.infn.it> 1213
>>>
>>> # Allow any path to be exported; this is further refined in the authfile.
>>> all.export / r/w
>>>
>>> # Hosts allowed to use this xrootd cluster
>>> cms.allow host *
>>> # Logging verbosity
>>> xrootd.trace emsg login stall redirect
>>> ofs.trace all -debug
>>> xrd.trace all -debug
>>> cms.trace all -debug
>>>
>>> cms.fxhold 8h
>>> xrd.sched maxt 16000
>>> ===
>>>
>>> but again , this is a sort of guess .... Do you have an example of a
>>> standalone cfg file for a supervisor?
>>>
>>>
>>> thanks
>>>
>>> tom
>>>
>>> http://xrootd.org/doc/dev42/cms_config.htm#_Toc405927050
>>>
>>> --
>>> Tommaso Boccali
>>> INFN Pisa
>>>
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>>>
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>>>
>
>
> -- 
> Tommaso Boccali
> INFN Pisa
>
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