Hi, recently, after upgrading our bacula server from CentOS 5.10 to CentOS 6.4, we have been hit by an upstream kernel bug.
in our bacula config we use the following tape device settings for some time. Maximum Block Size = 1024K Minimum Block Size = 32K after OS upgrade the tape mount failed most of the times 16-Nov 00:03 bacula-sd JobId 431441: Error: block.c:1002 Read error on fd=7 at file:blk 0:0 on device "Drive-1" (/dev/nst1). ERR=Device or resource busy. we got the same error using dd, but not always. it took me about one week to find the root cause of the problem. It is described at redhat (need a subscription to read all details) https://access.redhat.com/site/solutions/303123 There exists a kernel patch, but it is not released until now. There i found also a workaround which works for us: # cat /etc/modprobe.d/mt-st.conf options st max_sg_segs=64 See also the latest technical notes from RHEL 6.5: --- https://access.redhat.com/site/documentation/en-US/Red_Hat_Enterprise_Linux/6/html/6.5_Technical_Notes/devices_issues.html kernel component When using large block size (1MB), the tape driver sometimes returns an EBUSY error. To work around this problem, use a smaller block size, that is 256KB. --- I wrote this just to save u time when u experiment on tape block size >= 1024k on CentOS/RHEL 6.x. Best regards Ulrich -- Ulrich Leodolter <ulrich.leodol...@obvsg.at> Oesterreichische Bibliothekenverbund und Service GmbH Raimundgasse 1/3, A-1020 Wien Fax +43 1 4035158-30 Tel +43 1 4035158-21 Web http://www.obvsg.at ------------------------------------------------------------------------------ Shape the Mobile Experience: Free Subscription Software experts and developers: Be at the forefront of tech innovation. Intel(R) Software Adrenaline delivers strategic insight and game-changing conversations that shape the rapidly evolving mobile landscape. Sign up now. http://pubads.g.doubleclick.net/gampad/clk?id=63431311&iu=/4140/ostg.clktrk _______________________________________________ Bacula-devel mailing list Bacula-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bacula-devel
