So Patrick, the problem you reported is that in 4.6.1 xrdadler32 doesn’t trigger a server side checksum calculation when xrdadler32 reached to the redirector, and only trigger server side calculation when going directly to the data server?
I am running 4.4.0 for production and I don’t see this issue. I recently run into a similar issue on a test cluster with 4.6.1 and Andy told me that adding “xrootd.chksum xrdadler32” to the redirector should address this issue. That seems to work but I will try it again.
regards,
--
Wei Yang | [log in to unmask] | 650-926-3338(O)
On 8/16/17, 2:24 AM, "[log in to unmask] on behalf of Patrick McGuigan" <[log in to unmask] on behalf of [log in to unmask]> wrote:
>Hi,
>
>I ran into an issue with xrdadler32 that may or may not be a bug.
>
>
>My dataservers and redirector are running version xrootd 3.3.6
>
>The dataservers are configured with the line:
>
>xrootd.chksum max 4 adler32 /usr/bin/xrdadler32
>
>so that checksums are stored in the extended attributes of the native XFS file
>system. This works fine.
>
>
>Originally the redirector did not have a similar line but during debugging I added:
>xrootd.chksum adler32 /usr/bin/xrdadler32
>
>
>I had to reinstall a client machine (an SRM host) based on the OSG software
>stack. The installation brought in version 4.6.1 for xrootd-client,
>xrootd-fuse, xrootd-libs, xrootd-client-libs. Specifically the packages are:
><package>-4.6.1-1.osg33.el6.x86_64
>
>
>After installation I ran into problems with code that uses xrdadler32 to
>retrieve checksums from files that are normally mounted via xrootdfs. The code
>that uses xrdadler32 exports an XROOTD_VMP so that calls are translated to
>native xroot URL's. The problem was that the code was not retrieving the
>checksum, but instead, calculating the checksum on the SRM host which required
>the SRM host to read the entire file locally.
>
>
>I tracked this back a little bit and discovered that if I used
>/usr/bin/xrdadler32 with an xroot URL (with the redirector as host), then the
>checksum would be performed without a checksum being stored on the dataservers
>native file system using extended attributes. If the xroot URL used the correct
>dataserver as the host, then the checksum was stored.
>
>
>I downgraded the xrootd installation on the SRM host to version
>xrootd-client-4.5.0-2.osg33.el6.x86_64 and everything seems to be working properly.
>
>
>I am not sure if this is a bug, given the age of the dataserver installation,
>but I was encouraged to report it.
>
>Regards,
>
>Patrick
>
>########################################################################
>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
########################################################################
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
|