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NEX-9338 improve the layout of the crash directory
Reviewed by: Sanjay Nadkarni <sanjay.nadkarni@nexenta.com>
Reviewed by: Steve Peng <steve.peng@nexenta.com>
   1 SAVECORE(1M)                 Maintenance Commands                 SAVECORE(1M)
   2 
   3 
   4 
   5 NAME
   6        savecore - save a crash dump of the operating system
   7 
   8 SYNOPSIS
   9        /usr/bin/savecore [-Lvd] [-f dumpfile] [directory]
  10 
  11 
  12 DESCRIPTION
  13        The savecore utility saves a crash dump of the kernel (assuming that
  14        one was made) and writes a reboot message in the shutdown log. By
  15        default, it is invoked by the dumpadm service each time the system
  16        boots.
  17 
  18 
  19        Depending on the dumpadm(1M) configuration savecore saves either the
  20        compressed or uncompressed crash dump. The compressed crash dump is
  21        saved in the file directory/vmdump.n.  savecore saves the uncompressed
  22        crash dump data in the file directory/vmcore.n and the kernel's
  23        namelist in directory/unix.n. The trailing n in the pathnames is
  24        replaced by a number which grows every time savecore is run in that
  25        directory.

  26 
  27 
  28        Before writing out a crash dump, savecore reads a number from the file
  29        directory/minfree. This is the minimum number of kilobytes that must
  30        remain free on the file system containing directory. If after saving
  31        the crash dump the file system containing directory would have less
  32        free space the number of kilobytes specified in minfree, the crash dump
  33        is not saved. if the minfree file does not exist, savecore assumes a
  34        minfree value of 1 megabyte.
  35 
  36 
  37        The savecore utility also logs a reboot message using facility LOG_AUTH
  38        (see syslog(3C)). If the system crashed as a result of a panic,
  39        savecore logs the panic string too.
  40 
  41 OPTIONS
  42        The following options are supported:
  43 
  44        -d
  45                       Disregard dump header valid flag. Force savecore to


  66                       crash dumps can only be performed if you have configured
  67                       your system to have a dedicated dump device using
  68                       dumpadm(1M).
  69 
  70                       savecore -L does not suspend the system, so the contents
  71                       of memory continue to change while the dump is saved.
  72                       This means that live crash dumps are not fully self-
  73                       consistent.
  74 
  75 
  76        -v
  77                       Verbose. Enables verbose error messages from savecore.
  78 
  79 
  80 OPERANDS
  81        The following operands are supported:
  82 
  83        directory
  84                     Save the crash dump files to the specified directory. If
  85                     directory is not specified, savecore saves the crash dump
  86                     files to the default savecore directory, configured by
  87                     dumpadm(1M).

  88 
  89 
  90 FILES
  91        directory/vmdump.n
  92 
  93 
  94 
  95        directory/vmcore.n
  96 
  97 
  98 
  99        directory/unix.n
 100 
 101 
 102 
 103        directory/bounds
 104 
 105 
 106 
 107        directory/minfree
 108 
 109 
 110 
 111        /var/crash/`uname -n`
 112                                     default crash dump directory
 113 
 114 
 115 SEE ALSO
 116        adb(1), mdb(1), svcs(1), dd(1M), dumpadm(1M), svcadm(1M), syslog(3C),
 117        attributes(5), smf(5)
 118 
 119 NOTES
 120        The system crash dump service is managed by the service management
 121        facility, smf(5), under the service identifier:
 122 
 123          svc:/system/dumpadm:default
 124 
 125 
 126 
 127 
 128        Administrative actions on this service, such as enabling, disabling, or
 129        requesting restart, can be performed using svcadm(1M). The service's
 130        status can be queried using the svcs(1) command.
 131 
 132 
 133        If the dump device is also being used as a swap device, you must run
 134        savecore very soon after booting, before the swap space containing the
 135        crash dump is overwritten by programs currently running.
 136 
 137 
 138 
 139                                January 30, 2013                   SAVECORE(1M)
   1 SAVECORE(1M)                 Maintenance Commands                 SAVECORE(1M)
   2 
   3 
   4 
   5 NAME
   6        savecore - save a crash dump of the operating system
   7 
   8 SYNOPSIS
   9        /usr/bin/savecore [-Lvd] [-f dumpfile] [directory]
  10 
  11 
  12 DESCRIPTION
  13        The savecore utility saves a crash dump of the kernel (assuming that
  14        one was made) and writes a reboot message in the shutdown log. By
  15        default, it is invoked by the dumpadm service each time the system
  16        boots.
  17 
  18 
  19        Depending on the dumpadm(1M) configuration savecore saves either the
  20        compressed or uncompressed crash dump. The compressed crash dump is
  21        saved in the file directory/data/uuid/vmdump.n, where uuid is the OS
  22        instance UUID of the image that crashed.  savecore saves the
  23        uncompressed crash dump data in the file directory/data/uuid/vmcore.n
  24        and the kernel's namelist in directory/data/uuid/unix.n. The trailing n
  25        in the pathnames is replaced by a number which grows every time
  26        savecore is run in that directory.
  27 
  28 
  29        Before writing out a crash dump, savecore reads a number from the file
  30        directory/minfree. This is the minimum number of kilobytes that must
  31        remain free on the file system containing directory. If after saving
  32        the crash dump the file system containing directory would have less
  33        free space the number of kilobytes specified in minfree, the crash dump
  34        is not saved. if the minfree file does not exist, savecore assumes a
  35        minfree value of 1 megabyte.
  36 
  37 
  38        The savecore utility also logs a reboot message using facility LOG_AUTH
  39        (see syslog(3C)). If the system crashed as a result of a panic,
  40        savecore logs the panic string too.
  41 
  42 OPTIONS
  43        The following options are supported:
  44 
  45        -d
  46                       Disregard dump header valid flag. Force savecore to


  67                       crash dumps can only be performed if you have configured
  68                       your system to have a dedicated dump device using
  69                       dumpadm(1M).
  70 
  71                       savecore -L does not suspend the system, so the contents
  72                       of memory continue to change while the dump is saved.
  73                       This means that live crash dumps are not fully self-
  74                       consistent.
  75 
  76 
  77        -v
  78                       Verbose. Enables verbose error messages from savecore.
  79 
  80 
  81 OPERANDS
  82        The following operands are supported:
  83 
  84        directory
  85                     Save the crash dump files to the specified directory. If
  86                     directory is not specified, savecore saves the crash dump
  87                     to the default savecore directory, configured by
  88                     dumpadm(1M), and files are stored under distinct
  89                     directory/data/uuid folder.
  90 
  91 
  92 FILES
  93        directory/data/uuid/vmdump.n
  94 
  95 
  96 
  97        directory/data/uuid/vmcore.n
  98 
  99 
 100 
 101        directory/data/uuid/unix.n
 102 
 103 
 104 
 105        directory/bounds
 106 
 107 
 108 
 109        directory/minfree
 110 
 111 
 112 
 113        /var/crash/`uname -n`
 114                                     default crash dump directory
 115 
 116 
 117 SEE ALSO
 118        adb(1), mdb(1), svcs(1), dd(1M), dumpadm(1M), svcadm(1M), syslog(3C),
 119        attributes(5), smf(5)
 120 
 121 NOTES
 122        The system crash dump service is managed by the service management
 123        facility, smf(5), under the service identifier:
 124 
 125          svc:/system/dumpadm:default
 126 
 127 
 128 
 129 
 130        Administrative actions on this service, such as enabling, disabling, or
 131        requesting restart, can be performed using svcadm(1M). The service's
 132        status can be queried using the svcs(1) command.
 133 
 134 
 135        If the dump device is also being used as a swap device, you must run
 136        savecore very soon after booting, before the swap space containing the
 137        crash dump is overwritten by programs currently running.
 138 
 139 
 140 
 141                                 January 8, 2017                   SAVECORE(1M)