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US FAX S tatus Report. Wei Yang 2012-08-27. Site Status. Most sites are online and stable Observe successful failover between US and UK sites Via EU-BNL redirection bridge (mutual xrootd.redirect ) Observe sporadic crashing, debugging with OU Suspect there is minor opr issue at AGLT2.
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US FAX Status Report Wei Yang 2012-08-27
Site Status • Most sites are online and stable • Observe successful failover between US and UK sites • Via EU-BNL redirection bridge (mutual xrootd.redirect) • Observe sporadic crashing, debugging with OU • Suspect there is minor opr issue at AGLT2. • Observe large number of hosts joining FAX using 10.44.14.X • Need to enforce “cms.allowdomain_name • Need to update site configuration to send out redirection summary reports.
Need a new xrootd release • Xrootd failover redirection issue • Failover mechanism causes target redirector to respond slowly for files that exist. • Observed at SLAC Tier 2 xrootd storage • It happens after large number of failover (xrootd) redirection • FAX redirectors could be effected • Xrootd failover redirection is widely used in FAX • Refers to redirect via “xrootd.redirect” (so it is not CMSd redirection) • Xrootd monitoring • A bug prevents UPD packet from been sent out • Requests handled by sendfile() are not counted toward total bytes read. • On linux, >8k reads use sendfile() --- almost all sequential reads use large blocks, including file transfer via xrdcp, gridftp, etc.