# IBM(c) 2011 EPL license http://www.eclipse.org/legal/epl-v10.html #------------------------------------------------------- =head 1 xCAT plugin to handle xCAT UI service portal commands =cut #------------------------------------------------------- package xCAT_plugin::webportal; use strict; require xCAT::Utils; require xCAT::MsgUtils; require xCAT::zvmUtils; require xCAT::DBobjUtils; require IO::Socket::INET; use Getopt::Long; use Data::Dumper; use xCAT::Table; use xCAT::NodeRange; use XML::Simple; require XML::Parser; sub handled_commands { # In order for this to work, you need to run: ln -s /opt/xcat/bin/xcatclientnnr /opt/xcat/bin/webportal # xcatclientnnr allows command to run without a node range return { webportal => "webportal" }; } sub process_request { my $request = shift; my $callback = shift; my $sub_req = shift; my %authorized_cmds = ( 'lszvm' => \&lszvm, 'provzlinux' => \&provzlinux, 'clonezlinux' => \&clonezlinux, 'genhostip' => \&genhostip, 'getmaxvm' => \&getmaxvm, 'getuserprivilege' => \&getuserprivilege, 'lsgoldenimages' => \&lsgoldenimages ); # Check if the request is authorized split ' ', $request->{arg}->[0]; my $cmd = $_[0]; if ( grep { $_ eq $cmd } keys %authorized_cmds ) { my $func = $authorized_cmds{$cmd}; $func->( $request, $callback, $sub_req ); } else { $callback->( { error => "$cmd is not authorized!\n", errorcode => [1] } ); } } sub println { my $callback = shift; my $msg = shift; my %rsp; push @{ $rsp{info} }, $msg; xCAT::MsgUtils->message( 'I', \%rsp, $callback ); return; } sub lszvm { my ( $request, $callback, $sub_req ) = @_; # List the zVM and their respective HCP my $out = ""; my %pair; # Look in 'zvm' table my $tab = xCAT::Table->new( 'zvm', -create => 1, -autocommit => 0 ); my @results = $tab->getAllAttribsWhere( "nodetype='vm'", 'hcp', 'parent' ); foreach (@results) { if ( $_->{'hcp'} && $_->{'parent'} && !$pair{ $_->{'hcp'} } ) { # Save zVM:HCP pairing $pair{ $_->{'hcp'} } = $_->{'parent'}; # Print out zVM:HCP $out .= $_->{'parent'} . ":" . $_->{'hcp'} . "\n"; } } $callback->( { data => $out } ); } sub provzlinux { my ( $request, $callback, $sub_req ) = @_; my $group = $request->{arg}->[1]; my $hcp = $request->{arg}->[2]; my $img = $request->{arg}->[3]; my $owner = $request->{arg}->[4]; # Exit if missing inputs if ( !$group || !$hcp || !$img || !$owner ) { println( $callback, '(Error) Missing group, HCP, image, or owner' ); return; } # Check the max # of virtual machines allowed my $out = `tabdump nodetype -w nodetype.comments=~"owner:$owner"`; my @tmp = split( /\n/, $out ); my $usrVM = scalar(@tmp) - 1; $out = `webportal getmaxvm $owner`; $out =~ s/Max allowed: //g; my $maxVM = int($out); # Do not continue if the max # is reached if ($usrVM >= $maxVM) { println( $callback, "You have reached the maximum number of virtual machines allowed ($maxVM). Delete unused virtual machines or contact your system administrator request more virtual machines."); return; } # Get node OS base my $profile; my $arch; my $os; ( $profile, $arch, $os ) = getosimagedef( $callback, $img ); if ( $os =~ m/sp/i ) { @tmp = split( /sp/, $os ); } else { @tmp = split( /\./, $os ); } my $os_base = $tmp[0]; # Read in default disk pool and disk size /opt/zhcp/conf/default.conf on zHCP # pool = POOL3 # eckd_size = 10016 my $disk_pool; my $eckd_size; my $fba_size; my $profile_conf = $profile; my $default_conf = "/var/opt/xcat/profiles/$profile.conf"; my $default_direct = "/var/opt/xcat/profiles/$profile.direct"; # Check if a group based directory entry exists, else use default one if ( !(`test -e /var/opt/xcat/profiles/$profile.direct && echo Exists`) ) { println( $callback, "$profile.direct does not exist. Using default.direct to generate directory entry." ); # Exit if default.direct does not exist $default_direct = "/var/opt/xcat/profiles/default.direct"; $default_conf = "/var/opt/xcat/profiles/default.conf"; $profile_conf = "default"; if ( !(`test -e $default_direct && echo Exists`) ) { println( $callback, "(Error) $default_direct does not exists" ); return; } } # Exit if default.conf does not exist if ( !(`test -e $default_conf && echo Exists`) ) { println( $callback, "(Error) $default_conf does not exists" ); return; } # Exit if default.direct does not exist if ( !(`test -e $default_direct && echo Exists`) ) { println( $callback, "(Error) $default_direct does not exists" ); return; } $out = `cat $default_conf`; @tmp = split( /\n/, $out ); # default.conf should contain: # Configuration for virtual machines # default_diskpool=POOL3 # default_eckd_size=10016 my $profile_diskpool_parm = $profile_conf . "_diskpool"; my $profile_eckd_size_parm = $profile_conf . "_eckd_size"; my $profile_fba_size_parm = $profile_conf . "_fba_size"; my $default_disk_pool; my $default_eckd_size; my $default_fba_size; foreach (@tmp) { # Get profile disk pool (default) if ( $_ =~ m/$profile_diskpool_parm=/i ) { $disk_pool = $_; $disk_pool =~ s/$profile_diskpool_parm=//g; } # Get profile disk size (default) elsif ( $_ =~ m/$profile_eckd_size_parm=/i ) { $eckd_size = $_; $eckd_size =~ s/$profile_eckd_size_parm=//g; } elsif ( $_ =~ m/$profile_fba_size_parm=/i ) { $fba_size = $_; $fba_size =~ s/$profile_fba_size_parm=//g; } } # Use default configuration if profile configuration does not exist if (!$disk_pool && (!$eckd_size || !$fba_size)) { println( $callback, "(Error) $profile_conf configuration for disk pool and size does not exist" ); return; } my $site_tab = xCAT::Table->new('site'); my $hash = $site_tab->getAttribs( { key => "installdir" }, 'value' ); my $install_dir = $hash->{'value'}; # Get autoyast/kickstart template # Count the number of disks needed my $tmpl; if ( $os =~ m/sles/i ) { $tmpl = "$install_dir/custom/install/sles/$profile.$os_base.$arch.tmpl"; } elsif ( $os =~ m/rhel/i ) { $tmpl = "$install_dir/custom/install/rh/$profile.$os_base.$arch.tmpl"; } # Create VM # e.g. webportal provzlinux [group] [hcp] [image] # my ($node, $ip, $base_digit) = gennodename( $callback, $group ); my ($node, $ip, $hostname) = findfreenode( $callback, $group ); if (!$node) { println( $callback, "Unable to find a free node, IP, and hostname for $group from the IP pool" ); return; } my $userid = $node; # Set node definitions # Also put node into all group if ($group eq 'all') { $out = `mkdef -t node -o $node userid=$userid hcp=$hcp mgt=zvm groups=$group`; } else { # Put node in all group $out = `mkdef -t node -o $node userid=$userid hcp=$hcp mgt=zvm groups=$group`; } println( $callback, "$out" ); # Set nodetype definitions $out = `chtab node=$node hosts.ip=$ip hosts.hostnames=$hostname noderes.netboot=zvm nodetype.nodetype=osi nodetype.provmethod=install nodetype.os=$os nodetype.arch=$arch nodetype.profile=$profile nodetype.comments="owner:$owner"`; # Create user directory entry replacing LXUSR with user ID # Use /opt/zhcp/conf/default.direct on zHCP as the template # USER LXUSR PSWD 512M 1G G # INCLUDE LNXDFLT # COMMAND SET VSWITCH VSW2 GRANT LXUSR $out = `sed $default_direct -e s/LXUSR/$userid/g > /tmp/$node-direct.txt`; $out = `mkvm $node /tmp/$node-direct.txt`; `rm -rf /tmp/$node-direct.txt`; println( $callback, "$out" ); if ( $out =~ m/Error/i ) { return; } # Add MDISKs to user directory entry # Use /opt/zhcp/conf/default.conf on zHCP to determine disk pool and disk size # pool = POOL3 # eckd_size = 10016 my $type; my $virt_addr; if ( $os =~ m/sles/i ) { # Create XML object my $xml = new XML::Simple; # Read XML file my $data = $xml->XMLin($tmpl); my $devices_ref = $data->{'dasd'}->{'devices'}->{'listentry'}; my @devices; if (ref($devices_ref) eq 'HASH') { # In the case of 1 device in the listentry, push hash into array push(@devices, $devices_ref); } else { # Listentry is an array reference @devices = @$devices_ref; } foreach (@devices) { # Get disk virtual address and disk type $type = $_->{'drivers'}->{'listentry'}->{'modules'}->{'module_entry'}->{'listentry'}; $virt_addr = $_->{'sysfs_bus_id'}; $virt_addr =~ s/0\.0\.//g; foreach (@$type) { # Add ECKD disk if ( $_ =~ m/dasd_eckd_mod/i ) { $out = `chvm $node --add3390 $disk_pool $virt_addr $eckd_size MR`; println( $callback, "$out" ); if ( $out =~ m/Error/i ) { return; } } # Add FBA disk elsif ( $_ =~ m/dasd_fba_mod/i ) { # To be continued # $out = `chvm $node --add9336 $disk_pool $virt_addr $fba_size MR`; } } } # End of foreach } elsif ( $os =~ m/rhel/i ) { my %devices; my $dev; $virt_addr = 100; # Read in kickstart file $out = `cat $tmpl | egrep "part /"`; @tmp = split( /\n/, $out ); foreach (@tmp) { $out = substr( $out, index( $out, '--ondisk=' )+9 ); $out =~ s/\s*$//; # Trim right $out =~ s/^\s*//; # Trim left $devices{$out} = 1; } # Add ECKD disk for each device found for $dev ( keys %devices ) { $out = `chvm $node --add3390 $disk_pool $virt_addr $eckd_size MR`; println( $callback, "$out" ); if ( $out =~ m/Error/i ) { return; } # Increment virtual address $virt_addr = $virt_addr + 1; } } # Update hosts table and DNS `makehosts`; `makedns`; # Update DHCP `makedhcp -a`; # Toggle node power so COMMAND SET will get executed `rpower $node on`; `rpower $node off`; # Punch kernel, initrd, and ramdisk to node reader $out = `nodeset $node install`; println( $callback, "$out" ); if ( $out =~ m/Error/i ) { return; } # IPL reader and begin installation $out = `rnetboot $node ipl=00C`; println( $callback, "$out" ); if ( $out =~ m/Error/i ) { return; } # Configure Ganglia monitoring $out = `moncfg gangliamon $node -r`; # Show node information, e.g. IP, hostname, and root password $out = `lsdef $node -i ip,hostnames | egrep "ip=|hostnames="`; my $rootpw = getsysrootpw(); println( $callback, "Your virtual machine is ready. It may take a few minutes before you can logon using VNC ($node:1). Below is your VM attributes." ); println( $callback, "$out" ); println( $callback, " rootpw = $rootpw" ); } sub getsysrootpw { # Get the default root password for all xCAT provisioned VM my ( $callback ) = @_; my $tab = xCAT::Table->new('passwd'); my $hash = $tab->getAttribs( { key => "system" }, 'password' ); my $passwd = $hash->{'password'}; return $passwd; } sub getosimagedef { # Get osimage definitions based on image name my ( $callback, $img_name ) = @_; my $profile; my $arch; my $os; # Get profile, osarch, and osver in 'osimage' table based on imagename my $tab = xCAT::Table->new( 'osimage', -create => 1, -autocommit => 0 ); my @results = $tab->getAllAttribsWhere( "imagename='" . $img_name . "'", 'profile', 'osarch', 'osvers' ); foreach (@results) { # It should return: |gpok(\d+)|10.1.100.($1+0)| $profile = $_->{'profile'}; $arch = $_->{'osarch'}; $os = $_->{'osvers'}; } return ( $profile, $arch, $os ); } sub gennodename { # Generate node name based on given group my ( $callback, $group ) = @_; # Only use the 1st group if ($group =~ m/,/) { my @groups = split(',', $group); $group = @groups[0]; } # Hostname and IP address regular expressions my $hostname_regex; my $ipaddr_regex; my @comments; my $base_digit = 0; my $base_hostname; my $base_ipaddr; # Network, submask, submask prefix, and host ranges my $network = ""; my $mask; my $prefix; my $hosts_count; my $range_low = 1; my $range_high = 254; # Hostname and IP address generated my $hostname; my $ipaddr; my $tmp; my @args; # Get regular expression for hostname in 'hosts' table my $tab = xCAT::Table->new( 'hosts', -create => 1, -autocommit => 0 ); my @results = $tab->getAllAttribsWhere( "node='" . $group . "'", 'ip', 'comments' ); foreach (@results) { # It should return: |gpok(\d+)|10.1.100.($1+0)| @args = split( /\|/, $_->{'ip'} ); $hostname_regex = $args[1]; $ipaddr_regex = $args[2]; $base_hostname = $args[1]; $base_hostname =~ s/\(\S*\)/#/g; # Get the 10.1.100. $base_ipaddr = $args[2]; $base_ipaddr =~ s/\(\S*\)//g; # Get the ($1+0) $ipaddr_regex =~ s/$base_ipaddr//g; # Get the network within comments # It should return: "description: All machines; network: 10.1.100.0/24;" # This will help determine the 1st node in the group if none exists @comments = split( /|/, $_->{'comments'} ); foreach (@comments) { if ($_ =~ m/network:/i) { $network = $_; # Remove network header $network =~ s/network://g; # Trim network section $network =~ s/\s*$//; $network =~ s/^\s*//; # Extract network $tmp = rindex($network, '/'); if ($tmp > -1) { # Get submask prefix $prefix = substr($network, $tmp); $prefix =~ s|/||g; # Get the number of hosts possible using submask $hosts_count = 32 - int($prefix); # Minus network and broadcast addresses $hosts_count = 2 ** $hosts_count - 2; # Get network $network = substr($network, 0, $tmp); } # Extract base digit, which depends on the netmask used $base_digit = substr($network, rindex($network, '.') + 1); # 1st number in range is network $range_low = $base_digit + 1; # Get hosts range if ($tmp > -1) { $range_high = $base_digit + $hosts_count; } } } # End of foreach } # End of foreach # Generate hostname $hostname = $base_hostname; $hostname =~ s/#/$base_digit/g; # Generate IP address $ipaddr = $hostname; $ipaddr =~ s/$hostname_regex/$ipaddr_regex/gee; $ipaddr = $base_ipaddr . $ipaddr; # Get networks in 'networks' table $tab = xCAT::Table->new( 'networks', -create => 1, -autocommit => 0 ); my $entries = $tab->getAllEntries(); # Go through each network my $iprange; foreach (@$entries) { # Get network, mask, and range $network = $_->{'net'}; $mask = $_->{'mask'}; $iprange = $_->{'dynamicrange'}; # If the host IP address is in this subnet, return if (xCAT::NetworkUtils->ishostinsubnet($ipaddr, $mask, $network)) { # Exit loop last; } else { $network = ""; } } # Exit if no network exist for group if (!$network) { return; } # Find the network range for this group based on networks table my @ranges; if ($iprange) { @args = split( /;/, $iprange ); foreach (@args) { # If a network range exists if ($_ =~ m/-/) { @ranges = split( /-/, $_ ); $range_low = $ranges[0]; $range_high = $ranges[1]; # Get the low and high ends digit $range_low =~ s/$base_ipaddr//g; $range_high =~ s/$base_ipaddr//g; } } } # End of if ($iprange) # If no nodes exist in group # Set the base digit to the low end of the network range if ($range_low && $base_digit == 1) { $base_digit = $range_low; # Generate hostname $hostname = $base_hostname; $hostname =~ s/#/$base_digit/g; # Generate IP address $ipaddr = $hostname; $ipaddr =~ s/$hostname_regex/$ipaddr_regex/gee; $ipaddr = $base_ipaddr . $ipaddr; } # Check xCAT tables, /etc/hosts, and ping to see if hostname is already used while (`nodels $hostname` || `cat /etc/hosts | grep "$ipaddr "` || !(`ping -c 4 $ipaddr` =~ m/100% packet loss/)) { # Base digit invalid if over 254 if ($base_digit > $range_high) { last; } # +1 to base digit to obtain next hostname $base_digit = $base_digit + 1; $hostname = $base_hostname; $hostname =~ s/#/$base_digit/g; $ipaddr = $hostname; $ipaddr =~ s/$hostname_regex/$ipaddr_regex/gee; $ipaddr = $base_ipaddr . $ipaddr; } # Range must be within network range if ($base_digit > $range_high) { return; } else { return ($hostname, $ipaddr, $base_digit); } } sub clonezlinux { my ( $request, $callback, $sub_req ) = @_; # webportal clonezlinux [src node] [group] [owner] my $src_node = $request->{arg}->[1]; my $group = $request->{arg}->[2]; my $owner = $request->{arg}->[3]; # Check the max # of virtual machines allowed my $out = `tabdump nodetype -w nodetype.comments=~"owner:$owner"`; my @tmp = split( /\n/, $out ); my $usrVM = scalar(@tmp) - 1; $out = `webportal getmaxvm $owner`; $out =~ s/Max allowed: //g; my $maxVM = int($out); # Do not continue if the max # is reached if ($usrVM >= $maxVM) { println( $callback, "You have reached the maximum number of virtual machines allowed ($maxVM). Delete unused virtual machines or contact your system administrator request more virtual machines."); return; } # Get source node's HCP my $props = xCAT::zvmUtils->getNodeProps( 'zvm', $src_node, ('hcp') ); my $hcp = $props->{'hcp'}; # Get source node's nodetype $props = xCAT::zvmUtils->getNodeProps( 'nodetype', $src_node, ('os', 'arch', 'profile') ); my $os = $props->{'os'}; my $arch = $props->{'arch'}; my $profile = $props->{'profile'}; # Read in default disk pool from /var/opt/xcat/profiles/default.conf on xCAT MN # pool = POOL3 # eckd_size = 10016 my $disk_pool; my $default_conf = '/var/opt/xcat/profiles/default.conf'; my $default_direct = '/var/opt/xcat/profiles/default.direct'; # Exit if default.conf does not exist if ( !(`test -e $default_conf && echo Exists`) ) { println( $callback, '(Error) $default_conf does not exists' ); return; } # Exit if default.direct does not exist if ( !(`test -e $default_direct && echo Exists`) ) { println( $callback, '(Error) $default_direct does not exists' ); return; } $out = `cat $default_conf`; @tmp = split( /\n/, $out ); # default.conf should contain: # Default configuration for virtual machines handled by this zHCP # default_diskpool=POOL3 # compute_diskpool=POOL3 my $profile_diskpool_parm = ''; if ($profile) { $profile_diskpool_parm = $profile . "_diskpool"; } foreach (@tmp) { # Get disk pool (default) if ( $_ =~ m/default_diskpool=/i ) { $disk_pool = $_; $disk_pool =~ s/default_diskpool=//g; } # Get profile disk pool (default) elsif ( $_ =~ m/$profile_diskpool_parm=/i && $profile_diskpool_parm) { $disk_pool = $_; $disk_pool =~ s/$profile_diskpool_parm=//g; } } # Trim disk pool of white space $disk_pool =~ s/\s*$//; # Trim right $disk_pool =~ s/^\s*//; # Trim left # Create VM # e.g. webportal provzlinux [group] [hcp] [image] # my ($node, $ip, $base_digit) = gennodename( $callback, $group ); my ($node, $ip, $hostname) = findfreenode( $callback, $group ); if (!$node) { println( $callback, "Unable to find a free node, IP, and hostname for $group from the IP pool" ); return; } my $userid = $node; # Set node definitions $out = `mkdef -t node -o $node userid=$userid hcp=$hcp mgt=zvm groups=$group`; println( $callback, "$out" ); # Set nodetype definitions $out = `chtab node=$node hosts.ip=$ip hosts.hostnames=$hostname noderes.netboot=zvm nodetype.nodetype=osi nodetype.provmethod=install nodetype.os=$os nodetype.arch=$arch nodetype.profile=$profile nodetype.comments="owner:$owner"`; # Update hosts table and DNS sleep(5); # Time needed to update /etc/hosts `makehosts`; `makedns`; # Update DHCP `makedhcp -a`; println( $callback, "hosts table, DHCP, and DNS updated" ); # Clone virtual machine sleep(5); # Time needed to update /etc/hosts $out = `mkvm $node $src_node pool=$disk_pool`; println( $callback, "$out" ); if ( $out =~ m/Error/i || $out =~ m/Failed/i ) { return; } # Configure Ganglia monitoring $out = `moncfg gangliamon $node -r`; # Show node information, e.g. IP, hostname, and root password $out = `lsdef $node | egrep "ip=|hostnames="`; my $rootpw = getsysrootpw(); println( $callback, "Your virtual machine is ready. It may take a few minutes before you can logon. Below is your VM attributes." ); println( $callback, "$out" ); println( $callback, " rootpw = Same as source node" ); } sub genhostip { my ( $request, $callback, $sub_req ) = @_; my $group = $request->{arg}->[1]; # my ($node, $ip, $base_digit) = gennodename( $callback, $group ); my ($node, $ip, $hostname) = findfreenode( $callback, $group ); println( $callback, "$node: $ip, $hostname" ); } sub getmaxvm { my ( $request, $callback, $sub_req ) = @_; my $user = $request->{arg}->[1]; my @args; my $max; # Look in 'policy' table my $tab = xCAT::Table->new( 'policy', -create => 1, -autocommit => 0 ); my @results = $tab->getAllAttribsWhere( "name='" . $user . "'", 'comments' ); foreach (@results) { if ( $_->{'comments'} ) { @args = split( ';', $_->{'comments'} ); # Extract max VM foreach (@args) { if ($_ =~ m/max-vm:/i) { $_ =~ s/max-vm://g; $max = $_; last; } } } } $callback->( { data => "Max allowed: $max" } ); } sub getuserprivilege { # Get the user privilege my ( $request, $callback, $sub_req ) = @_; my $user = $request->{arg}->[1]; if (!$user) { $callback->( { data => "(Error) No user name is specified" } ); return; } my @args; my $privilege = "user"; # Look in 'policy' table my $tab = xCAT::Table->new( 'policy', -create => 1, -autocommit => 0 ); my @results = $tab->getAllAttribsWhere( "name='" . $user . "'", 'comments' ); foreach (@results) { if ( $_->{'comments'} ) { @args = split( ';', $_->{'comments'} ); # Extract user privilege foreach (@args) { if ($_ =~ m/privilege:/i) { $_ =~ s/privilege://g; $privilege = $_; $privilege =~ s/\s*$//; # Trim right $privilege =~ s/^\s*//; # Trim left last; } } } } $callback->( { data => "Privilege: $privilege" } ); } sub lsgoldenimages { my ( $request, $callback, $sub_req ) = @_; # Find the golden image that can be cloned by searching nodetype table for nodetype.provmethod=clone my $clones = ""; my $comments = ""; my $description = ""; my @args; # Look in 'policy' table my $tab = xCAT::Table->new( 'nodetype', -create => 1, -autocommit => 0 ); my @results = $tab->getAllAttribsWhere( "provmethod='clone'", 'node', 'comments' ); foreach (@results) { if ($_->{'node'}) { $clones .= $_->{'node'} . ": "; $comments = $_->{'comments'}; @args = split(';', $comments); foreach (@args) { if ($_ =~ m/description:/i) { $description = $_; $description =~ s/description://g; $description =~ s/\s*$//; # Trim right $description =~ s/^\s*//; # Trim left } else { $description = "No comments"; } } $clones .= $description . ","; } } # Delete last comma $clones = substr($clones, 0, -1); $callback->( { data => $clones } ); } sub findfreenode { # Generate node name based on given group my ( $callback, $group ) = @_; # IP pool contained in /var/opt/xcat/ippool where a file exists per group if ( !(`test -e /var/opt/xcat/ippool/$group.pool && echo Exists`) ) { return; } # IP pool group format: node, IP, hostname # It would look similar to: # ihost10,10.1.136.10,ihost10.endicott.ibm.com # ihost11,10.1.136.11,ihost11.endicott.ibm.com # ihost12,10.1.136.12,ihost12.endicott.ibm.com my $node; my $ipaddr; my $hostname; my $out = `cat /var/opt/xcat/ippool/$group.pool | grep -v "#"`; my @entries = split( /\n/, $out ); if (@entries < 1) { return; } my $found = 0; foreach(@entries) { # Grab the 1st free entry found ($node, $ipaddr, $hostname) = split(/,/, $_); if ($node && $ipaddr && $hostname) { # Check against xCAT tables, /etc/hosts, and ping to see if hostname is already used if (`nodels $node` || `cat /etc/hosts | grep "$ipaddr "` || !(`ping -c 4 $ipaddr` =~ m/100% packet loss/)) { next; } else { $found = 1; return ($node, $ipaddr, $hostname); } } } return; } 1;