Patch Name: PHCO_13198 Patch Description: s700_800 10.20 dd(1) patch for block/unblock conversion Creation Date: 97/11/25 Post Date: 97/11/25 Hardware Platforms - OS Releases: s700: 10.20 s800: 10.20 Products: N/A Filesets: OS-Core.UX-CORE Automatic Reboot?: No Status: General Release Critical: No Path Name: /hp-ux_patches/s700_800/10.X/PHCO_13198 Symptoms: PHCO_13198: When using conv=block/unblock, the output buffer is flushed at cbs, rather than obs. Assuming cbs is much smaller than obs (which it normally is), this means the file is written in relatively small chunks, requiring a much larger number of writes to complete the data copy. The user can see this reflected in the dd(1) output; for "records out", it is likely to show 0 (zero) full records and a large number of partial records. This problem is especially significant when the output file is a tape device, where inter-record gaps (IRGs) occur between writes. This could result in the user reaching end-of-tape very unexpectedly. Defect Description: PHCO_13198: dd(1) gives incorrect results when conv=block or conv=unblock is used and cbs < obs. (And under normal circumstances, cbs is very likely to be less than obs.) For "records out", dd(1) shows 0 (zero) full records and a large number of partial records. This is an especially significant issue if the output file is a tape device, where the user may reach end-of-tape very unexpectedly as a result of the driver inserting inter-record gaps (IRGs) between output records. SR: 1653209940 Patch Files: /usr/bin/dd what(1) Output: /usr/bin/dd: $Revision: 78.2.1.1 $ PATCH_10_20: dd.o 97/11/25 cksum(1) Output: 4202436784 28672 /usr/bin/dd Patch Conflicts: None Patch Dependencies: None Hardware Dependencies: None Other Dependencies: None Supersedes: None Equivalent Patches: None Patch Package Size: 80 KBytes Installation Instructions: Please review all instructions and the Hewlett-Packard SupportLine User Guide or your Hewlett-Packard support terms and conditions for precautions, scope of license, restrictions, and, limitation of liability and warranties, before installing this patch. ------------------------------------------------------------ 1. Back up your system before installing a patch. 2. Login as root. 3. Copy the patch to the /tmp directory. 4. Move to the /tmp directory and unshar the patch: cd /tmp sh PHCO_13198 5a. For a standalone system, run swinstall to install the patch: swinstall -x autoreboot=true -x match_target=true \ -s /tmp/PHCO_13198.depot 5b. For a homogeneous NFS Diskless cluster run swcluster on the server to install the patch on the server and the clients: swcluster -i -b This will invoke swcluster in the interactive mode and force all clients to be shut down. WARNING: All cluster clients must be shut down prior to the patch installation. Installing the patch while the clients are booted is unsupported and can lead to serious problems. The swcluster command will invoke an swinstall session in which you must specify: alternate root path - default is /export/shared_root/OS_700 source depot path - /tmp/PHCO_13198.depot To complete the installation, select the patch by choosing "Actions -> Match What Target Has" and then "Actions -> Install" from the Menubar. 5c. For a heterogeneous NFS Diskless cluster: - run swinstall on the server as in step 5a to install the patch on the cluster server. - run swcluster on the server as in step 5b to install the patch on the cluster clients. By default swinstall will archive the original software in /var/adm/sw/patch/PHCO_13198. If you do not wish to retain a copy of the original software, you can create an empty file named /var/adm/sw/patch/PATCH_NOSAVE. Warning: If this file exists when a patch is installed, the patch cannot be deinstalled. Please be careful when using this feature. It is recommended that you move the PHCO_13198.text file to /var/adm/sw/patch for future reference. To put this patch on a magnetic tape and install from the tape drive, use the command: dd if=/tmp/PHCO_13198.depot of=/dev/rmt/0m bs=2k Special Installation Instructions: None