Provided by: pdsh_2.34-3build2_amd64 bug

NAME

       pdsh - issue commands to groups of hosts in parallel

SYNOPSIS

       pdsh [options]... command

DESCRIPTION

       pdsh  is  a  variant of the rsh(1) command. Unlike rsh(1), which runs commands on a single
       remote host, pdsh can run multiple remote commands  in  parallel.  pdsh  uses  a  "sliding
       window" (or fanout) of threads to conserve resources on the initiating host while allowing
       some connections to time out.

       When pdsh receives SIGINT (ctrl-C), it lists the  status  of  current  threads.  A  second
       SIGINT  within  one  second  terminates  the  program.  Pending threads may be canceled by
       issuing ctrl-Z within one second of ctrl-C.  Pending threads are those that have  not  yet
       been initiated, or are still in the process of connecting to the remote host.

       If  a  remote  command  is  not  specified  on  the command line, pdsh runs interactively,
       prompting for commands and executing them when  terminated  with  a  carriage  return.  In
       interactive  mode,  target  nodes that time out on the first command are not contacted for
       subsequent commands, and commands prefixed with an exclamation point will be  executed  on
       the local system.

       The  core  functionality  of pdsh may be supplemented by dynamically loadable modules. The
       modules may provide a new connection protocol (replacing  the  standard  rcmd(3)  protocol
       used  by  rsh(1)),  filtering options (e.g. removing hosts that are "down" from the target
       list), and/or host selection options (e.g., -a selects  all  hosts  from  a  configuration
       file.). By default, pdsh must have at least one "rcmd" module loaded. See the RCMD MODULES
       section for more information.

RCMD MODULES

       The method by which pdsh runs commands on remote hosts may be selected  at  runtime  using
       the  -R  option  (See  OPTIONS  below).   This functionality is ultimately implemented via
       dynamically loadable modules, and so the list of available options may be  different  from
       installation  to  installation. A list of currently available rcmd modules is printed when
       using any of the -h, -V, or -L options. The default rcmd module  will  also  be  displayed
       with the -h and -V options.

       A list of rcmd modules currently distributed with pdsh follows.

       rsh     Uses  an internal, thread-safe implementation of BSD rcmd(3) to run commands using
               the standard rsh(1) protocol.

       exec    Executes an arbitrary command for each target host. The first of the  pdsh  remote
               arguments is the local command to execute, followed by any further arguments. Some
               simple parameters are substitued on the command line, including %h for the  target
               hostname,  %u  for the remote username, and %n for the remote rank [0-n] (To get a
               literal % use %%).  For example, the  following  would  duplicate  using  the  ssh
               module to run hostname(1) across the hosts foo[0-10]:

                  pdsh -R exec -w foo[0-10] ssh -x -l %u %h hostname

               and   this   command   line  would  run  grep(1)  in  parallel  across  the  files
               console.foo[0-10]:

                  pdsh -R exec -w foo[0-10] grep BUG console.%h

       ssh     Uses a variant of popen(3) to run multiple copies of the ssh(1) command.

       mrsh    This module uses the mrsh(1) protocol to execute jobs on remote hosts.   The  mrsh
               protocol  uses  a  credential  based authentication, forgoing the need to allocate
               reserved ports. In other aspects, it acts just like  rsh.  Remote  nodes  must  be
               running mrshd(8) in order for the mrsh module to work.

       krb4    The  krb4 module allows users to execute remote commands after authenticating with
               kerberos. Of course, the remote rshd daemons must be kerberized.

       xcpu    The xcpu module uses the xcpu service to execute remote commands.

OPTIONS

       The list of available options is determined  at  runtime  by  supplementing  the  list  of
       standard  pdsh options with any options provided by loaded rcmd and misc modules.  In some
       cases, options provided by modules may conflict with  each  other.  In  these  cases,  the
       modules are incompatible and the first module loaded wins.

Standard target nodelist options

       -w TARGETS,...
              Target  and  or  filter the specified list of hosts. Do not use with any other node
              selection options (e.g. -a, -g, if they are available). No spaces  are  allowed  in
              the  comma-separated  list.   Arguments in the TARGETS list may include normal host
              names, a range of hosts in hostlist format (See HOSTLIST EXPRESSIONS), or a  single
              `-' character to read the list of hosts on stdin.

              If a host or hostlist is preceded by a `-' character, this causes those hosts to be
              explicitly excluded. If the argument is preceded by a single `^' character,  it  is
              taken  to be the path to file containing a list of hosts, one per line. If the item
              begins with a `/' character, it is taken  as  a  regular  expression  on  which  to
              filter  the  list  of  hosts  (a  regex  argument may also be optionally trailed by
              another '/', e.g.  /node.*/). A regex or file name argument may also  be  preceeded
              by a minus `-' to exclude instead of include thoses hosts.

              A  list of hosts may also be preceded by "user@" to specify a remote username other
              than the default, or "rcmd_type:" to specify an alternate rcmd connection type  for
              these  hosts.  When  used  together,  the  rcmd  type must be specified first, e.g.
              "ssh:user1@host0" would use ssh to connect to host0 as user "user1."

       -x host,host,...
              Exclude the specified hosts. May be specified in conjunction with other target node
              list options such as -a and -g (when available). Hostlists may also be specified to
              the -x option (see the HOSTLIST EXPRESSIONS section below).  Arguments  to  -x  may
              also  be  preceeded  by  the filename (`^') and regex ('/') characters as described
              above, in which case the resulting hosts are excluded as if they had been given  to
              -w and preceeded with the minus `-' character.

Standard pdsh options

       -S     Return the largest of the remote command return values.

       -h     Output  usage  menu and quit. A list of available rcmd modules will also be printed
              at the end of the usage message.

       -s     Only on AIX, separate remote command stderr and stdout into two sockets.

       -q     List option values and the target nodelist and exit without action.

       -b     Disable ctrl-C status feature so that a single ctrl-C kills  parallel  job.  (Batch
              Mode)

       -l user
              This  option  may  be  used  to  run  remote  commands  as another user, subject to
              authorization. For BSD rcmd, this means the invoking user and system must be listed
              in the userĀ“s .rhosts file (even for root).

       -t seconds
              Set  the  connect  timeout. Default is 10 seconds.  This option may also be set via
              the PDSH_CONNECT_TIMEOUT environment variable.

       -u seconds
              Set a limit on the amount of time a remote command is allowed to execute.   Default
              is no limit. See note in LIMITATIONS if using -u with ssh.  This option may also be
              set via the PDSH_COMMAND_TIMEOUT environment variable.

       -f number
              Set the maximum number of simultaneous remote commands to number.  The  default  is
              32.

       -R name
              Set  rcmd  module  to  name.  This  option  may  also be set via the PDSH_RCMD_TYPE
              environment variable. A list of available rcmd modules may be obtained via the  -h,
              -V, or -L options.  The default will be listed with -h or -V.

       -M name,...
              When  multiple  misc  modules  provide  the  same options to pdsh, the first module
              initialized "wins" and subsequent modules are not loaded.  The -M option  allows  a
              list  of  modules to be specified that will be force-initialized before all others,
              in-effect ensuring that they load  without  conflict  (unless  they  conflict  with
              eachother).  This  option  may  also  be  set via the PDSH_MISC_MODULES environment
              variable.

       -L     List info on all loaded pdsh modules and quit.

       -N     Disable hostname: prefix on lines of output.

       -d     Include more complete thread status when SIGINT is received,  and  display  connect
              and command time statistics on stderr when done.

       -V     Output  pdsh  version information, along with list of currently loaded modules, and
              exit.

machines module options

       -a     Target all nodes from machines file.

genders module options

       In addition to the genders options presented below, the genders  attribute  pdsh_rcmd_type
       may  also  be  used in the genders database to specify an alternate rcmd connect type than
       the pdsh default for hosts with this attribute. For example, the  following  line  in  the
       genders file

         host0 pdsh_rcmd_type=ssh

       would  cause  pdsh to use ssh to connect to host0, even if rsh were the default.  This can
       be overridden on the commandline with the "rcmd_type:host0" syntax.

       -A     Target all nodes in genders database. The -A option will target every  host  listed
              in genders -- if you want to omit some hosts by default, see the -a option below.

       -a     Target  all  nodes  in  genders  database  except  those  with  the "pdsh_all_skip"
              attribute. This is shorthand for running "pdsh -A -X pdsh_all_skip ..."

       -g attr[=val][,attr[=val],...]
              Target nodes that match any of the  specified  genders  attributes  (with  optional
              values).  Conflicts  with  the  -a  option.  If used in combination with other node
              selection options like -w, the -g option will select from the supplied  node  list,
              instead  of  from  the  genders file as a whole. Otherwise, This option targets the
              alternate hostnames in the genders database by default. The -i option  provided  by
              the  genders  module  may  be  used  to  translate  these  to the canonical genders
              hostnames. If the installed version of genders supports it, attributes supplied  to
              -g  may  also  take  the  form  of  genders queries. Genders queries will query the
              genders database for the union, intersection, difference, or complement of  genders
              attributes  and values.  The set operation union is represented by two pipe symbols
              ('||'), intersection by two ampersand  symbols  ('&&'),  difference  by  two  minus
              symbols ('--'), and complement by a tilde ('~').  Parentheses may be used to change
              the order of operations. See  the  nodeattr(1)  manpage  for  examples  of  genders
              queries.

       -X attr[=val][,attr[=val],...]
              Exclude  nodes  that match any of the specified genders attributes (optionally with
              values).  This option may be used  in  combination  with  any  other  of  the  node
              selection  options  (e.g. -w, -g, -a, -X may also take the form of genders queries.
              Please see documentation for the genders  -g  option  for  more  information  about
              genders queries.

       -i     Request translation between canonical and alternate hostnames.

       -F filename
              Read  genders information from filename instead of the system default genders file.
              If filename doesn't specify an absolute path then it is taken to be relative to the
              directory specified by the PDSH_GENDERS_DIR environment variable (/etc by default).
              An  alternate  genders  file  may  also  be  specified  via  the  PDSH_GENDERS_FILE
              environment variable.

nodeupdown module options

       -v     Eliminate target nodes that are considered "down" by libnodeupdown.

slurm module options

       The  slurm  module  allows pdsh to target nodes based on currently running SLURM jobs. The
       slurm module is typically  called  after  all  other  node  selection  options  have  been
       processed,  and  if no nodes have been selected, the module will attempt to read a running
       jobid from the SLURM_JOBID environment variable (which is set when running under  a  SLURM
       allocation). If SLURM_JOBID references an invalid job, it will be silently ignored.

       -j jobid[,jobid,...]
              Target  list  of  nodes  allocated  to the SLURM job jobid. This option may be used
              multiple times to target multiple SLURM jobs. The special  argument  "all"  can  be
              used to target all nodes running SLURM jobs, e.g.  -j all.

       -P partition[,partition,...]
              Target  list of nodes containing in the SLURM partition partition.  This option may
              be used multiple times to target multiple SLURM partitions and/or partitions may be
              given in a comma-delimited list.

torque module options

       The  torque module allows pdsh to target nodes based on currently running Torque/PBS jobs.
       Similar to the slurm module, the torque module is typically called after  all  other  node
       selection options have been processed, and if no nodes have been selected, the module will
       attempt to read a running jobid from the PBS_JOBID environment variable (which is set when
       running under a Torque allocation).

       -j jobid[,jobid,...]
              Target  list  of  nodes  allocated to the Torque job jobid. This option may be used
              multiple times to target multiple Torque jobs.

dshgroup module options

       The dshgroup module allows pdsh to use dsh (or Dancer's  shell)  style  group  files  from
       /etc/dsh/group/  or  ~/.dsh/group/.  The  default  search  path may be overridden with the
       DSHGROUP_PATH environment variable, a colon-separated list of directories to  search.  The
       default value for DSHGROUP_PATH is /etc/dsh/group.

       -g groupname,...
              Target  nodes  in dsh group file "groupname" found in either ~/.dsh/group/groupname
              or /etc/dsh/group/groupname.

       -X groupname,...
              Exclude nodes in dsh group file "groupname."

       As an enhancement in pdsh, dshgroup files may optionally include other dshgroup files  via
       a  special #include STRING syntax.  The argument to #include may be either a file path, or
       a group name, in which case the path used to search for the group file is the same  as  if
       the group had been specified to -g.

netgroup module options

       The  netgroup module allows pdsh to use standard netgroup entries to build lists of target
       hosts. (/etc/netgroup or NIS)

       -g groupname,...
              Target nodes in netgroup "groupname."

       -X groupname,...
              Exclude nodes in netgroup "groupname."

ENVIRONMENT VARIABLES

       PDSH_RCMD_TYPE
              Equivalent to the -R option, the value of this environment variable will be used to
              set the default rcmd module for pdsh to use (e.g. ssh, rsh).

       PDSH_SSH_ARGS
              Override  the  standard arguments that pdsh passes to the ssh(1) command ("-2 -a -x
              -l%u %h"). The use of the parameters %u, %h, and %n (as documented in the rcmd/exec
              section  above) is optional. If these parameters are missing, pdsh will append them
              to the ssh commandline because it is assumed they are mandatory.

       PDSH_SSH_ARGS_APPEND
              Append additional options to the ssh(1) command  invoked  by  pdsh.   For  example,
              PDSH_SSH_ARGS_APPEND="-q"  would  run ssh in quiet mode, or "-v" would increase the
              verbosity of ssh.  (Note:  these  arguments  are  actually  prepended  to  the  ssh
              commandline to ensure they appear before any target hostname argument to ssh.)

       WCOLL  If  no  other  node selection option is used, the WCOLL environment variable may be
              set to a filename from which a list of target hosts will be read. The  file  should
              contain  a  list  of  hosts,  one per line (though each line may contain a hostlist
              expression.  See HOSTLIST EXPRESSIONS section below).

       DSHPATH
              If set, the path in DSHPATH will be used as the PATH for the remote processes.

       FANOUT Set the pdsh fanout (See description of -f above).

HOSTLIST EXPRESSIONS

       As noted in sections above pdsh accepts lists of hosts  the  general  form:  prefix[n-m,l-
       k,...],  where  n  < m and l < k, etc., as an alternative to explicit lists of hosts. This
       form should not be confused with regular expression character  classes  (also  denoted  by
       ``[]'').  For example, foo[19] does not represent an expression matching foo1 or foo9, but
       rather represents the degenerate hostlist: foo19.

       The hostlist syntax is meant only as a convenience on clusters with a  "prefixNNN"  naming
       convention  and  specification  of  ranges  should not be considered necessary -- the list
       foo1,foo9 could be specified as such, or by the hostlist foo[1,9].

       Some examples of usage follow:

       Run command on foo01,foo02,...,foo05
           pdsh -w foo[01-05] command

       Run command on foo7,foo9,foo10
            pdsh -w foo[7,9-10] command

       Run command on foo0,foo4,foo5
            pdsh -w foo[0-5] -x foo[1-3] command

       A suffix on the hostname is also supported:

       Run command on foo0-eth0,foo1-eth0,foo2-eth0,foo3-eth0
          pdsh -w foo[0-3]-eth0 command

       As a reminder to the reader, some shells will interpret brackets ('[' and ']') for pattern
       matching.   Depending  on  your  shell, it may be necessary to enclose ranged lists within
       quotes.  For example, in tcsh, the first example above should be executed as:

            pdsh -w "foo[01-05]" command

ORIGIN

       Originally a rewrite of IBM dsh(1) by Jim Garlick <garlick@llnl.gov> on LLNL's ASCI  Blue-
       Pacific IBM SP system. It is now used on Linux clusters at LLNL.

LIMITATIONS

       When using ssh for remote execution, expect the stderr of ssh to be folded in with that of
       the remote command. When invoked by pdsh, it  is  not  possible  for  ssh  to  prompt  for
       passwords  if  RSA/DSA  keys  are configured properly, etc..  For ssh implementations that
       suppport a connect timeout option, pdsh attempts to use that option to enforce the timeout
       (e.g.  -oConnectTimeout=T  for OpenSSH), otherwise connect timeouts are not supported when
       using ssh.  Finally, there is no reliable way for pdsh to ensure that remote commands  are
       actually terminated when using a command timeout. Thus if -u is used with ssh commands may
       be left running on remote hosts even after timeout has killed local ssh processes.

       The number of nodes that pdsh can simultaneously execute remote jobs on is limited by  the
       maximum number of threads that can be created concurrently, as well as the availability of
       reserved ports in the rsh module. On systems that implement Posix threads,  the  limit  is
       typically defined by the constant PTHREADS_THREADS_MAX.

FILES

SEE ALSO

       rsh(1), ssh(1), dshbak(1), pdcp(1)

                                            linux-gnu                                     pdsh(1)