xcat-core/xCAT-SoftLayer/bin/modifygrub

279 lines
9.6 KiB
Perl
Executable File

#!/usr/bin/perl
# Modify the grub config file on the node to boot the specified kernel and initrd.
# This script is meant to be run on the node via xdsh -e.
# Currently requires that dns on the mn be configured and working to resolve the short node names.
use strict;
use Getopt::Long;
use Data::Dumper;
use Socket;
# Globals - these are set once and then only read.
my $HELP;
my $VERBOSE;
my $WAITTIME;
my $XCATNETBOOTTITLE = 'xCAT network boot kernel and initrd';
my $usage = sub {
my $exitcode = shift @_;
print "Usage: modifygrub [-?|-h|--help] [-v|--verbose] [-w <waittime>] <kernel-path> <initrd-path> <kernel-parms> <mn-ip>\n\n";
if (!$exitcode) {
print "Modify the grub config file on the node to boot the specified kernel and initrd.\n";
}
exit $exitcode;
};
if (-f '/etc/os-release') { die "This script doesn't support ubuntu yet.\n"; }
# Process the cmd line args
Getopt::Long::Configure("bundling");
#Getopt::Long::Configure("pass_through");
Getopt::Long::Configure("no_pass_through");
if (!GetOptions('h|?|help' => \$HELP, 'v|verbose' => \$VERBOSE, 'w|waittime=s' => \$WAITTIME)) { $usage->(1); }
if ($HELP) { $usage->(0); }
if (scalar(@ARGV) != 4) { $usage->(1); }
if (!defined($WAITTIME)) { $WAITTIME = 60; } # seconds to wait after configuring the nic (to let the switch handle the state change)
my %args;
$args{kernelpath} = $ARGV[0];
$args{initrdpath} = $ARGV[1];
$args{kernelparms} = $ARGV[2];
$args{mnip} = $ARGV[3];
addKernelParms(\%args); # replace and add some parms to args{kernelparms}
updateGrub(\%args); # update the grub config with an entry filled with the info in args
exit(0);
# Add ip and net info to the kernel parms. Modifies the kernelparms value of the args hash passed in.
sub addKernelParms {
my $args = shift @_;
# replace '!myipfn!' with the mn ip
my $mnip = $args->{mnip};
$args->{kernelparms} =~ s/!myipfn!/$mnip/g;
# replace <nodename> with the nodename
my $nodename = $ENV{NODE}; # this env var is set by xdsh
$args->{kernelparms} =~ s/<nodename>/$nodename/g;
# get node ip and add it to the kernel parms
my ($nic, $ip, $netmask, $gateway, $mac) = getNodeIpInfo($args);
if (!$ip) { die "Error: could not find the NIC that would connect to the xCAT mgmt node's IP (".$args->{mnip}.").\n"; }
# if we are booting genesis, need to add the BOOTIF parm
my $bootif;
if ($args->{kernelpath} =~ m/genesis\.kernel\.x86_64/) {
$bootif = $mac;
$bootif =~ s/:/-/g;
$bootif = "BOOTIF=01-$bootif";
}
$args->{kernelparms} .= " $bootif hostip=$ip netmask=$netmask gateway=$gateway dns=$mnip hostname=$nodename netdevice=$nic netwait=$WAITTIME textmode=1";
}
# get this nodes nic, ip, netmask, gateway, and mac. Returns them in a 5 element array.
sub getNodeIpInfo {
my $args = shift @_;
my ($ipprefix) = $args->{mnip}=~m/^(\d+\.\d+)\./; #todo: this is a hack, just using the 1st 2 octets of the mn ip addr
verbose("using IP prefix $ipprefix");
# parse ip addr show output, looking for ipprefix, to determine nic and ip
my @output = runcmd("ip addr show");
my ($nic, $mac, $ipandmask);
foreach my $line (@output) {
my ($nictmp, $mactmp, $iptmp);
if (($nictmp) = $line=~m/^\d+:\s+(\S+): /) { $nic = $nictmp; } # new stanza, remember it
if (($mactmp) = $line=~m|^\s+link/ether\s+(\S+) |) { $mac = $mactmp; } # got mac, remember it
if (($iptmp) = $line=~m/^\s+inet\s+($ipprefix\S+) /) { $ipandmask = $iptmp; last; } # got ip, we are done
}
my ($ip, $netmask) = convertIpAndMask($ipandmask);
# if the nic is a bonded nic (common on sl), then find the 1st real nic that is part of it
my $realnic = $nic;
if ($nic =~ /^bond/) {
my @nics = grep(m/\s+master\s+$nic\s+/, @output);
if (!scalar(@nics)) { die "Error: can't find the NICs that are part of $nic.\n"; }
($realnic) = $nics[0]=~m/^\d+:\s+(\S+): /;
# go back thru the ip add show output and find the mac of this nic
foreach my $line (@output) {
my ($nictmp, $mactmp, $foundnic);
if (($nictmp) = $line=~m/^\d+:\s+(\S+): / && $nictmp eq $realnic) { $foundnic = 1; }
if (($mactmp) = $line=~m|^\s+link/ether\s+(\S+) | && $foundnic) { $mac = $mactmp; last; } # got mac, we are done
}
}
# finally, find the gateway
my $gateway;
my @output = runcmd("ip route");
# we are looking for a line like: 10.0.0.0/8 via 10.54.51.1 dev bond0
my @networks = grep(m/ via .* $nic\s*$/, @output);
if (scalar(@networks)) { ($gateway) = $networks[0]=~m/ via\s+(\S+)/; }
else {
# use the mn ip as a fall back
$gateway = $args->{mnip};
verbose("using xCAT mgmt node IP as the fall back gateway.");
}
verbose("IP info: realnic=$realnic, ip=$ip, netmask=$netmask, gateway=$gateway, mac=$mac");
return ($realnic, $ip, $netmask, $gateway, $mac);
}
# Convert an ip/mask in slash notation (like 10.0.0.1/26) to separate ip and netmask like 10.0.0.1 and 255.255.255.192
sub convertIpAndMask {
my $ipandmask = shift @_;
my ($ip, $masknum) = split('/', $ipandmask);
my $netbin = oct("0b" . '1' x $masknum . '0' x (32-$masknum)); # create a str like '1111100', then convert to binary
my @netarr=unpack('C4',pack('N',$netbin)); # separate into the 4 octets
my $netmask=join('.',@netarr); # put them together into the normal looking netmask
return ($ip, $netmask);
}
# not used - resolve the hostname to an ip addr
sub getipaddr {
my $hostname = shift @_;
my $packed_ip;
$packed_ip = inet_aton($hostname);
if (!$packed_ip) { return undef; }
return inet_ntoa($packed_ip);
}
# Update the grub config file with a new stanza for booting our kernel and initrd
sub updateGrub {
my $args = shift @_;
# how we specify the path for the kernel and initrd is different on redhat and suse
my $fileprefix;
if (isRedhat()) { $fileprefix = '/'; }
elsif (isSuse()) { $fileprefix = '/boot/'; }
else { die "Error: currently only support red hat or suse distros.\n"; }
# open the grub file and see if it is in there or if we have to add it
my $grubfile = findGrubPath();
verbose("reading $grubfile");
open(FILE, $grubfile) || die "Error: can not open config file $grubfile for reading: $!\n";
my @lines = <FILE>;
close FILE;
# this is the entry we want in the grub file
my @rootlines = grep(/^\s+root\s+/, @lines); # copy one of the existing root lines
if (!scalar(@rootlines)) { die "Error: can't find an existing line for 'root' in the grub config file\n"; }
my ($rootline) = $rootlines[0] =~ m/^\s*(.*?)\s*$/;
my @entry = (
"title $XCATNETBOOTTITLE\n",
"\t$rootline\n",
"\tkernel " . $fileprefix . $args->{kernelpath} . ' ' . $args->{kernelparms} . "\n",
"\tinitrd " . $fileprefix . $args->{initrdpath} . "\n",
);
my $needtowritefile = 1;
if (grep(/^title\s+$XCATNETBOOTTITLE/, @lines)) { $needtowritefile = updateGrubEntry(\@lines, \@entry); } # there is already an entry in there
else { addGrubEntry (\@lines, \@entry); }
# write the file with the new/updated xcat entry
if ($needtowritefile) {
verbose("updating $grubfile");
open(FILE, '>', $grubfile) || die "Error: can not open config file $grubfile for writing: $!\n";
print FILE @lines;
close FILE;
}
else { print "Info: $grubfile did not need modifying. It was already up to date.\n"; }
}
# add our entry as the 1st one in the grub file
sub addGrubEntry {
my ($lines, $entry) = @_;
# find the index of the 1st stanza (it starts with 'title')
my $i;
for ($i=0; $i<scalar(@$lines); $i++) {
if ($lines->[$i] =~ m/^title\s+/) { verbose('adding xcat entry before:'.$lines->[$i]); last; } # found it
}
# splice the entry right before the i-th line (which may also be 1 past the end)
splice(@$lines, $i, 0, @$entry);
}
# check the xcat entry in the grub file and see if it needs to be updated. Return 1 if it does.
sub updateGrubEntry {
my ($lines, $entry) = @_;
#print Dumper($lines), Dumper($entry);
# find the index of the xcat stanza
my $i;
for ($i=0; $i<scalar(@$lines); $i++) {
if ($lines->[$i] =~ m/^title\s+$XCATNETBOOTTITLE/) { last; } # found it
}
# compare the next few lines with the corresponding line in @$entries and replace if different
my $replaced = 0;
for (my $j=0; $j<scalar(@$entry); $j++) {
#print "comparing:\n ", $lines->[$i+$j], "\n ", $entry->[$j], "\n";
if ($lines->[$i+$j] ne $entry->[$j]) { # this line was different
$lines->[$i+$j] = $entry->[$j];
$replaced = 1;
}
}
return $replaced;
}
# depending on the distro, find the correct grub file and return its path
sub findGrubPath {
# for rhel/centos it is /boot/grub/grub.conf, for sles it is /boot/grub/menu.lst
my @paths = qw(/boot/grub/grub.conf /boot/grub/menu.lst);
foreach my $p (@paths) {
if (-f $p) { return $p; }
}
die "Error: Can't find grub config file.\n";
#todo: support ubuntu: you add an executable file in /etc/grub.d named 06_xcatnetboot that prints out the
# entry to add. Then run grub-mkconfig.
}
# Pring msg only if -v was specified
sub verbose { if ($VERBOSE) { print shift, "\n"; } }
# Check the distro we are running on
sub isSuse { return (-e '/etc/SuSE-release'); }
sub isRedhat { return (-e '/etc/redhat-release' || -e '/etc/centos-release' || -e '/etc/fedora-release'); } # add chk for fedora
# Run a command. If called in the context of return an array, it will capture the output
# of the cmd and return it. Otherwise, it will display the output to stdout.
# If the cmd has a non-zero rc, this function will die with a msg.
sub runcmd
{
my ($cmd) = @_;
my $rc;
$cmd .= ' 2>&1' ;
verbose($cmd);
my @output;
if (wantarray) {
@output = `$cmd`;
$rc = $?;
}
else {
system($cmd);
$rc = $?;
}
if ($rc) {
$rc = $rc >> 8;
if ($rc > 0) { die "Error: rc $rc return from cmd: $cmd\n"; }
else { die "Error: system error returned from cmd: $cmd\n"; }
}
elsif (wantarray) { return @output; }
}