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Hi Fabrizio, I've been working on XCache integration of ATLAS and had the same problem as you do. The xrootd client plugin provides a fast solution of using different urls for reading/writing. https://github.com/feipengsy/XrdCLROProxyPlugin After installing the client-side plugin above (and configuring /etc/xrootd/client.plugins.d/ProxyRW-plugin.conf), the url of reading activity will be prefixed with the XCache server address while the url of writing stays unchanged. That's currently I'm doing tests with. Hope it could help. Cheers, Teng Quoting Fabrizio Furano <[log in to unmask]> on Fri, 2 Mar 2018 10:29:59 +0100: > Hi Andy, > > thanks for the hints. My opinion is that a passthrough option would be > a very big plus for the caching proxy, and I was sincerely surprised > by this limitation. > > For some of our use cases I believe that we will start using it without > caching, as I can't imagine how to give a transparent service by having > to force clients to use different paths for reading and writing. > > What do you think ? > > Thank you > Fabrizio > > On 03/01/2018 06:09 PM, Andrew Hanushevsky wrote: >> Correct, we don't support a writable cache because that's not what >> a cache is all about. Does the origin support writes? If so, >> we could potentially provide a cache passthrough option. Otherwise, >> if the readable and writable path differ, he could have run >> two proxies -- one caching for read access and a passthru proxy for >> writing then setup a redirect directive in the primary proxy >> (i.e. the one that will be initially used) to direct writes to the >> passthru proxy based on path. >> >> Andy >> >> On Thu, 1 Mar 2018, Fabrizio Furano wrote: >> >>> Hi, >>> >>> Mihai is trying to setup a small Pss machine that also works as a cache. >>> >>> For reading it seems to work fine, yet it stubbornly refuses to >>> write files with >>> this error: >>> >>>> 180301 17:27:38 13788 XrdFileCache_Manager: debug Cache::Attach() >>>> root:[log in to unmask]:1094//eos/xdc/testing/hello.txt?&oss.asize=14&oss.lcl=1 location: <deferred >>>> open> >>>> 180301 17:27:38 13788 root.3008:20@xdc-test-fst1 ofs_fstat: >>>> fn=/eos/xdc/testing/hello.txt >>>> 180301 17:27:38 13788 root.3008:20@xdc-test-fst1 XrootdResponse: >>>> 0100 sending 46 data bytes; status=0 >>>> 180301 17:27:38 13788 root.3008:20@xdc-test-fst1 XrootdProtocol: >>>> 0100 req=write dlen=14 >>>> 180301 17:27:38 13788 root.3008:20@xdc-test-fst1 XrootdProtocol: >>>> 0100 fh=0 write 14@0 >>>> 180301 17:27:38 13788 root.3008:20@xdc-test-fst1 ofs_write: 14@0 >>>> fn=/eos/xdc/testing/hello.txt >>>> 180301 17:27:38 13788 ofs_write: root.3008:20@xdc-test-fst1 >>>> Unable to write /eos/xdc/testing/hello.txt; operation not supported >>>> 180301 17:27:38 13788 root.3008:20@xdc-test-fst1 XrootdProtocol: >>>> 0100 discarding 0 bytes >>>> 180301 17:27:38 13788 root.3008:20@xdc-test-fst1 XrootdResponse: >>>> 0100 sending err 3005: Unable to write >>>> /eos/xdc/testing/hello.txt; operation not supported >>>> 180301 17:27:38 13788 root.3008:20@xdc-test-fst1 XrootdProtocol: >>>> 0100 req=close dlen=0 >>>> 180301 17:27:38 13788 root.3008:20@xdc-test-fst1 ofs_close: use=1 >>>> fn=/eos/xdc/testing/hello.txt >>> >>> If we remove the directive pss.cachelib then writes work instead. >>> >>> Can anyone give us a clue please ? >>> >>> Thank you >>> Fabrizio and Mihai >>> >>> >> > > > ######################################################################## > Use REPLY-ALL to reply to list > > To unsubscribe from the XROOTD-L list, click the following link: > https://listserv.slac.stanford.edu/cgi-bin/wa?SUBED1=XROOTD-L&A=1 > ---------------------------------------------------------------------- Teng LI, PDRA School of Physics and Astronomy, University of Edinburgh Email: [log in to unmask] Telephone: +44 (0) 742 2910721 Room 5412, James Clerk Maxwell Building, Kings Buildings, Peter Guthrie Tait Road Edinburgh EH9 3FD, United Kingdom ---------------------------------------------------------------------- -- The University of Edinburgh is a charitable body, registered in Scotland, with registration number SC005336. ######################################################################## Use REPLY-ALL to reply to list To unsubscribe from the XROOTD-L list, click the following link: https://listserv.slac.stanford.edu/cgi-bin/wa?SUBED1=XROOTD-L&A=1