Categories
Apache Linux Network Technologies Perl Raspberry Pi

Getting started on my Raspberry Pi

Intro
The Raspberry Pi computer is an awesome idea. Its performance is surprisingly good as well, as I will show below. Available packages? Not so impressive. I share some old X-windows tricks which will allow you to bring up the GUI without ever using the HDMI port.

The details
My Methodology
I was too lazy to set up an HDMI console plus keyboard and mouse. I’m more a server guy anyways so I’m more interested in what I can accomplish from a command prompt. And this also makes getting started that much easier. I had burned the Raspbian Wheezy image to a super-fast SD card (more on that below) the day that my Pi came in the mail. I attached power and ethernet, booted it up, guessed the IP it acquired by running some PINGs, did an ssh using the pi/raspberry user and Bingo! I was in. It couldn’t be easier. How I tested GUI applications without a console is explained further down below.

First Impressions
It feels fast.

Packages
Not much seems to be there by default – no apache, not many X utilities. There is a lame X browser called x-www-browser. I thought this is Debian, right? So we can just start downloading Debian packages, like Firefox. Wrong! It doesn’t work that way. There’s no Firefox, Safari, Chrome or Opera! It does come pre-loaded with curl, however, ha, ha.

No, the Raspbian FAQ explains why this is. It’s rather complicated. I guess the compiler works though I haven’t tested it yet. So I suppose you could compile packages from their source code.

The x-terminal-emulator is pretty decent, however.

If it comes with a web server, I didn’t notice. So I quickly checked for the availability of apache. It’s available. Then installed it:

> sudo apt-get install apache2

That worked out well. It installed it and the packages it depended on and even launched it, and it all felt fairly peppy. See the suggested fix further down if this gives you errors. The default HTML DOCROOT is /var/www. I accessed it locally:

> curl localhost

And a welcome message displayed. A good start.

Where’s the rest of my 16 GB SD card gone to?

Original disk layout:

pi@raspberrypi:~$ df -k
Filesystem     1K-blocks    Used Available Use% Mounted on
rootfs           1804128 1492908    219572  88% /
/dev/root        1804128 1492908    219572  88% /
devtmpfs          224436       0    224436   0% /dev
tmpfs              44900     204     44696   1% /run
tmpfs               5120       0      5120   0% /run/lock
tmpfs              89780       0     89780   0% /run/shm
/dev/mmcblk0p1     57288   16872     40416  30% /boot

Layout after raspi-config:

pi@raspberrypi:~$ df -k
Filesystem     1K-blocks    Used Available Use% Mounted on
rootfs          15251960 1494852  12982544  11% /
/dev/root       15251960 1494852  12982544  11% /
devtmpfs          224436       0    224436   0% /dev
tmpfs              44900     196     44704   1% /run
tmpfs               5120       0      5120   0% /run/lock
tmpfs              89780       0     89780   0% /run/shm
/dev/mmcblk0p1     57288   16872     40416  30% /boot

Whew! That was easy. All 16 GB accounted for and actively used.

Was it worth it to buy that UHS SD card?
I didn’t want a sluggish server, so I paid a couple bucks more and bought a 16 GB SD UHS (ultra high speed) card for my “disk,” not knowing whether or not the Pi had the muscle to put it to work.

A quick aside about SD cards
I did a quickie self-education on this topic. Most SD cards are rated by class, so a class 4 SD card can do 4 MB/sec I/O, and a class 10 card can do at least 10 MB/sec. Faster still are the UHS SD cards. My Sandisk, which only cost about $19, is rated for 45 MB/sec I/O.

diskSpec.pl benchmark (higher numbers are better)
1333 file creation/destruction operations per second – Raspberry Pi with UHS SD card
6666 file creation/destruction operations per second – EBS volume on small image running CentOS in Amazon cloud
26000 file creation/destruction operations per second – high-end HP server (G7 DL380) running SLES 11

I think I provided the source for this simple Perl program I wrote, diskSpec.pl. It creates a file, writes a random number into it, then deletes it – that all counts as one operation. Here it is:

#!/usr/bin/perl
# DrJ, 1/2000
# Test disk I/O
$DIR = $ARGV[0];
chdir($DIR);
$t0 = time();
while(1) {
  $ran = rand();
  open(FILE,">$ran") || die "Cannot open file $ran in directory $DIR!!\n";
  print FILE $ran;
  close(FILE);
  unlink($ran);
  $cnt++;
  if ($cnt % 20000 == 0) {
    $rate = $cnt / (time() - $t0) ;
    print "File creation/desctruction rate: $rate\n";
  }
}

DrJ 2017 Note: The notes below are historical and does not seem to work at all for the Raspberry Pi 3 loaded with NOOBS. In NOOBS you select your OS to install. You can’t ssh to it. I know. I just tried! Even after you install Raspbian Wheezy, you still can’t access it via ssh until you enable the ssh daemon with raspi-condfig.

How to get the GUI working without a console
I have this feeling that many people trying out the Pi won’t have the faintest idea how X windows works, unlike us Unix old-timers. It’s fun to put 20-year-old lessons to work on something new. Like I said I’m lazy and didn’t feel the need to set up an actual console to the thing. I used some old X features to allow me to launch specific X-windows applications that are pre-loaded on the device, and display them on my PC. How?

On a Windows PC you install Cygwin. Then launch the XWin Server. You ssh to your pi. How do you know its IP the first time? Guess! It picks it up via DHCP, so start PINGing around the range where your other devices are numbered. My PC is 192.168.5.12/24, my pi was 192.168.5.16. Maybe you have a bunch of devices responding to PING and are unsure which is which? Your MAC table is your friend. Here’s mine:

C:\Documents and Settings>arp -a
 
Interface: 192.168.5.12 --- 0x2
  Internet Address      Physical Address      Type
  192.168.5.1           00-14-f6-e0-c0-4c     dynamic
  192.168.5.16          b8-27-eb-dd-21-02     dynamic
  192.168.5.99          00-90-a9-bb-3d-76     dynamic

arp displays the MAC table with the IP-to-physical (MAC) address correspondence. So most Pi’s will have a MAC address whose beginning is similar to b8-27-eb. A quick aside. Does the MAC address follow the board (SOC) or the SD Card? The board – I tested this with a friend’s SD Card.

You login with the pi/raspberry.

Then set your DISPLAY environment variable:

> export DISPLAY=192.168.5.12:0

Most of your X applications begin with the letter “x,” so enter

> x<tab><tab>

to see a display of available programs like this:

xapian-config        xdg-screensaver      xkbevd               xpdf.real            xxd
xarchiver            xdg-settings         xkbprint             xprop                xz
xargs                xdpyinfo             xkbvleds             x-session-manager    xzcat
xauth                xdriinfo             xkbwatch             xsubpp               xzcmp
xdg-desktop-icon     xev                  xkill                xtables-multi        xzdiff
xdg-desktop-menu     xfd                  xlsatoms             x-terminal-emulator  xzegrep
xdg-email            xfontsel             xlsclients           xvinfo               xzfgrep
xdg-icon-resource    xinit                xlsfonts             x-window-manager     xzgrep
xdg-mime             xkbbell              xmessage             xwininfo             xzless
xdg-open             xkbcomp              xpdf                 x-www-browser        xzmore

Actually I don’t know how many of these are X. But at least a few are.

Start an xterm in Cygwin. In the xterm window, give permission to the Pi to use it as its Xserver:

> xhost +

Now in the Pi shell (ha, ha), type:

> x-terminal-emulator

and you should see the colorful terminal emulator on your PC in a few seconds. this is a true GUI application. You similarly launch the x-www-browser. Don’t forget to background your X-windows in the Pi shell:

<Ctrl-Z>
> bg

so you can use the one window to launch multiple X windows.

Another example the book Programming the Raspberry Pi has is the Python interactive development environment. I reasoned from the screen shots that idles3 would also be an X application – hey, they don’t have to start with the letter x – and indeed it is!

Want the whole ball of wax, a complete console? I just figured this one out by taking an educated guess:

> x-session-manager

and you will see the complete GUI on your PC! Cool, huh?

Want to get rid of the last thing you backgrounded, like, say, that x-session-mnager which has taken over your PC?! Type

> fg
<Ctrl-C>

and it will be killed.

How to get the GUI working without a console, Method 2
The above steps look a little daunting? Even I don’t want to install cygwin on my new PC. There is an alternative which can suffice for light usage.

On the Pi install a vnc server:

$ sudo apt-get install tightvncserver

Launch it:

$ vncserver

The first time only it will ask you to set up a password. Might as well make it raspberry like everything else we do on the Pi.

Then install a VNC client on your PC (Or Macbook). I use RealVNC.

Launch your VNC client and connect to your Pi’s IP address (which you need to know) + the display number, like this:

192.168.0.100:1

For a Pi at IP 192.168.0.100 in which the vncserver started display 1. Normally it will be display 1, but I guess it might be display 0.

Don’t launch vncserver more than once! You don’t want a bunch of those running and dragging on performance.

Anyways, that’s it! You should see the Pi’s GUI on your PC, but it might seem a wee bit small.

Setting a static IP
If you’re going to use the Pi more as a server like I am, I think it’s a good idea to give it a static IP. What I did is to edit /etc/network/interfaces. Mine now looks like this:

# DrJ change: make IP static
# somewhat inspired by http://www.techiecorner.com/486/how-to-setup-static-ip-in-debian/
#iface eth0 inet dhcp
auto lo
auto eth0
iface eth0 inet static
address 192.168.5.100
gateway  192.168.5.1
netmask 255.255.255.0
network 192.168.5.0
broadcast 192.168.5.255

Network Utilities
It doesn’t come with much beyond ssh, curl and nc. I quickly downloaded stuff I like: telnet, ftp, tcpdump, dnsutils, lsof and nmap. That seemed to work out. I used apt-get install name . I recently read even Nagios can be installed! That’s pretty cool – it’s a sophisticated network monitoring utility.

Get a decent browser
The web browsers that come with the Pi are horrible. Midori? Seriously? I found you can get Firefox, but the downside is that it’s sloooww. But at least it works. The secret is that it’s not called Firefox. Instead:

$ sudo apt-get install iceweasel

Yes, it’s iceweasel, not Firefox, in Debian Linux. Go figure.

My cool transparent case
I recommend to get a case. I got the one with the best reviews. It’s kind of expensive, about $20, but worth it. It’s practically a work-of-art. Clear, the PC board fits snugly. I put it in my pocket and showed it around to my friends, feeling it was well protected, and yet also a sight to behold the first time. I even has a thoughtful light guide so the LEDs look beautiful as their light follows the rectangular opening to open air. I never had this much fun in show-and-tell! I just pulled the Pi wrapped in its case from my shirt pocket and amazed those around me. So go ahead and splurge. Anyways some of the cheaper cases look just that. Here is what I bought:

Helping a friend out with his Pi
So I dutifully take my friend’s Pi home and offer to install a web server. What did I do wrong? Well, duh, I could have just taken his SD Card home and plugged it into my Pi case! That concept takes some getting used to! We all have the same hardware. Our SD cards – our disk – are what make one Pi different from another.

So I followed my own blog post to recall some things. This Pi also had a MAC address beginning with the same six characters.

The apache2 installation did not work out, however. What to do? Well, I eventually read the darn output from running it. It suggests to try this:

> sudo apt-get update

So I ran that, figuring it could do no harm. Then I re-ran

> sudo apt-get install apache2

and this time the install actually worked!

Reading a flash drive
I was curious to see if you could stick a flash drive in the thing and just read it. I didn’t think so since I thought it would be formatted for NTFS. But if you have the GUI running and bring up a file manager, I’ll be darned if it doesn’t just work. I noticed the drive is mounted as /media/Cruzer (my flash drive has the brand name Cruzer).

If you don’t launch the file manager, I think you can still work with it as follows:

$ sudo mkdir /media/Cruzer; sudo mount /dev/sda1 /media/Cruzer

Then when you’re all done and before you remove it:

$ sudo umount /media/Cruzer

So that’s pretty cool. You can create tar archives on the flash drive, plug it into someone else’s Pi and untar it, etc, just like on Windows.

Conclusion
Raspberry Pi is respectable as a computer. It will be a lot of fun to explore for the hobbyist.

References
Go here for my next project – using your Raspberry Pi to monitor your home’s power or Internet connection.
Interested in networking? A lot of useful tips can be found in this posting describing how to turn your Pi into a router.
Realvnc.com distributes realVNC viewers for various platforms.
How about a Raspberry Pi-driven digital photo frame? I describe an approach in this article.
Brief Nagios for Raspberry Pi writeup.

Categories
Admin Perl Web Site Technologies

Turning HP SiteScope into SiteScope Classic with Perl

Intro
HP siteScope is a terrific web application tool and not too expensive for those who have any kind of a budget. The built-in monitor types are a bit limited, but since it allows calls to user-provided scripts your imagination is the only real limitation. For those with too many responsibilities and too little time on their hands it is a real productivity enhancer.

I’ve been using the product for 12 years now – since it was Freshwater SiteScope. I still have misgivings about the interface change introduced some years ago when it was part of Mercury. It went from simple and reliable to Java, complicated and flaky. To this day I have to re-start a SiteScope screen in my browser on a daily basis as the browser cannot recover from a server restart or who knows what other failures.

So I longed for the days of SiteScope Classic. We kept it running for as long as possible, years in fact. But at some point there were no more releases created for the classic view. So I investigated the feasibility of creating my own conversion tool. And…partially succeeded. Succeeded to the point where I can pull up the web page on my Blackberry and get the statuses and history. Think you can do that with regular HP SiteScope? I can’t. Maybe there’s an upgrade for it, but still. It’s nice to have the classic interface when you want to pull up the statuses as quickly as possible, regardless of the Blackberry display issue.

Looking back at my code, I obviously decided to try my hand at OO (object oriented) programming in Perl, with mixed results. Perl’s OO syntax isn’t the best, which addles comprehension. Without further ado, let’s jump into it.

The Details
It relies on something I noticed, that this URL on your HP SiteScope server, http://localhost:8080/SiteScope/services/APIConfigurationImpl?method=getConfigurationSnapshot, contains a tree of relationships of all the monitors. Cool, right? But it’s not a tree like you or I would design. Between parent and child is an intermediate layer. I suppose you need that because a group can contain monitors (my only focus in this exercise), but it can also contain alerts and maybe some other properties as well. So I guess the intermediate layer gives them the flexibility to represent all that, though it certainly added to my complication in parsing it. That’s why you’ll see the concern over “grandkids.” I developed a recursive, web-enabled Perl program to parse through this xml. That gives me the tools to build the nice hierarchical groupings. But it does not give me the statuses.

For the status of each monitor I wrote a separate scraper script that simply reads the entire daily SiteScope log every minute! Crude, but it works. I use it for an installation with hundreds of monitors and a log file that grows to 9 MB by the end of the day so I know it scales to that size. Beyond that it’s untested.

In addition to giving only the relationships, the xml also changes with every invocation. It attaches ID numbers to the monitors which initially you think is a nice unique identifier, but they change from invocation to invocation! So an additional challenge was to match up the names of the monitors in the xml output to the names as recorded in the SiteScope log. Also a bit tricky, but in general doable.

So without further ado, here’s the source code for the xml parser and main program which gets called from the web:

#!/usr/bin/perl
# Copyright work under the Artistic License, http://www.opensource.org/licenses/Artistic-2.0
# build v.simple SiteScope web GUI appropriate for smartphones
# 7/2010
#
# Id is our package which defines th Id class
use Id;
use CGI::Pretty;
my $cgi=new CGI;
$DEBUG = 0;
# GIF location on SiteScope classic
$ssgifs = "/artwork/";
$health{good} = qq(<img src="${ssgifs}okay.gif">);
$health{error} = qq(<img src="${ssgifs}error.gif">);
$health{warning} = qq(<img src="${ssgifs}warning.gif">);
# report CGI
$rprt = "/SS/rprt";
# the frustrating thing is that this xml output changes almost every time you call it
$url = 'http://localhost:8080/SiteScope/services/APIConfigurationImpl?method=getConfigurationSnapshot';
# get current health of all monitors - which is scraped from the log every minute by a hilgarj cron job
$monitorstats = "/tmp/monitorstats.txt";
print "Content-type: text/plain\n\n" if $DEBUG;
open(MONITORSTATS,"$monitorstats") || die "Cannot open monitor stats file $monitorstats!!";
while(<MONITORSTATS>) {
  chomp;
  ($monitor,$status,$value) = /([^\t]+)\t([^\t]+)\t([^\t]+)/;
  $monitors{"$monitor"} = $status;
  $monitorv{"$monitor"} = $value;
}
open(CURL,"curl $url 2>/dev/null|") || die "cannot open $url for reading!!\n";
my %myobjs = ();
# the xml is one long line!
@lines = <CURL>;
#print "xml line: $lines[0]\n" if $DEBUG;
@multiRefs = split "<multiRef",$lines[0];
#parse multiRefs
# create top-level object
my $id = Id->new (
      id => "id0");
# hash of this object with id as key
$myobjs{"id0"} = $id;
 
# first build our objects...
foreach $mref (@multiRefs) {
  next unless $mref =~ /\sid=/;
#  id="id0" ...
  ($parentid) =  $mref =~ /id=\"(id\d+)/;
  print "parentid: $parentid\n" if $DEBUG;
# watch out for <item><key xsi:type="soapenc:string">groupSnapshotChildren</key><value href="#id3 ...
# vs <item><key xsi:type="soapenc:string">Network</key><value href="#id40"/>
  print "mref: $mref\n" if $DEBUG;
  @ids = split /<item><key/, $mref;
# then loop over ids mentioned in this mref
  foreach $myid (@ids) {
    next unless $myid =~ /href="#(id\d+)/;
    next unless $myobjs{"$parentid"};
# types include group, monitor, alert
    ($typebyregex) = $myid =~ />snapshot_(\w+)SnapshotChildren</;
    $parenttype = $myobjs{"$parentid"}->type();
    $type = $typebyregex ? $typebyregex : $parenttype;
    print "type: $type\n" if $DEBUG;
# skip alert definitions
    next if $type eq "alert";
    print "myid: $myid\n" if $DEBUG;
    ($actualid) = $myid =~ /href="#(id\d+)/;
    print "actualid: $actualid\n" if $DEBUG;
# construct object
    my $id = Id->new (
      id => $actualid,
      type => $type,
      parentid => $parentid );
# build hash of these objects with actualid as key
    $myobjs{$actualid} = $id;
# addchild to parent. note that parent should already have been encountered
    $myobjs{"$parentid"}->addchild($actualid);
    if ($myid !~ /groupSnapshotChildren/) {
# interesting child - has name (every other generation has no name!)
      ($name) = $myid =~ /string\">(.+?)<\/key/;  # use non-greedy operator
      print "name: $name\n" if $DEBUG;
# some names are not of interest to us: alerts, which end in "error" or "good"
      if ($name !~ /(error|good)$/) {
# name may not be unique - get extended name which include all parents
        if (defined $myobjs{"$parentid"}->parentid()) {
          $gdparid = $myobjs{"$parentid"}->parentid();
          $gdparname = $myobjs{"$gdparid"}->extname();
# extname -> extended, or distinguished name.  Should be unique
          $extname = $gdparname. '/' . $name;
        } else {
# 1st generation
          print "1st generation\n" if $DEBUG;
          $extname = $name;
        }
        print "extname: $extname\n" if $DEBUG;
        $id->name($name);
        $id->extname($extname);
        $id->isanamedid(1);
        $myobjs{"$parentid"}->hasnamedkids(1); # want to mark its parent as "special"
# we also need our hash to reference objects by extended name since id changes with each extract and name
may not be unique
        $myobjs{"$extname"} = $id;
      } # end conditional over desirable name check
    } else {
      $id->isanamedid(0);
    }
  }
}
#
# now it's all parsed and our objects are alive. Let's build a web site!
#
# build a cookie containing path
my $pi = $ENV{PATH_INFO};
$script = $ENV{SCRIPT_NAME};
$ua = $ENV{HTTP_USER_AGENT};
# Blackberry browser test
$BB = $ua =~ /^BlackBerry/i ? 1 : 0;
$MSIE = $ua =~ /MSIE /;
# font-size depends on browser
$FS = "font-size: x-small;" if $MSIE;
$cookie = $cgi->cookie("pathinfo");
$uri = $script . $pi;
$cookie=$cgi->cookie(-name=>"pathinfo", -value=>"$uri");
print $cgi->header(-type=>"text/html",-cookie=>$cookie);
($url) = $pi =~ m#([^/]+)$#;
#  -title=>'SmartPhone View',
# this doesn't work, sigh...
#print $cgi->start_html(-head=>meta({-http_equiv=>'Refresh'}));
print qq( <HEAD>
<meta http-equiv="Expires" content="0">
<meta http-equiv="Pragma" content="no-cache">
<meta HTTP-EQUIV="Refresh" CONTENT="60; URL=$url">
<TITLE>SiteScope Classic $url Detail</TITLE>
<style type="text/css">
a.good {color: green; }
a.warning {color: green; }
a.error {color: red; }
td {font-family: Arial, Helvetica, sans-serif; $FS}
p.ss {font-family: Arial, Helvetica, sans-serif;}
</style>
<link rel="shortcut icon" href="/favicon.ico" type="image/x-icon" />
<script type=text/javascript>
function changeme(elemid,longvalue)
{
document.getElementById(elemid).innerText=longvalue;
}
function restoreme(elemid,truncvalue)
{
document.getElementById(elemid).innerText=truncvalue;
}
</script>
</HEAD><body>
);
 
#print $cgi->h1("This is the heading");
# parse path
# top lvl name:2nd lvl name:3rd lvl name
$altpi = $cgi->path_info();
print $cgi->p("pi is $pi") if $DEBUG;
#print $cgi->p("altpi is $altpi");
# relative url
$rurl = $cgi->url(-relative=>1);
if ($pi eq "") {
# the top
# top id is id3
  print qq(<p class="ss">);
  $myid = "id3";
  foreach $kid ($myobjs{"$myid"}->get_children()) {
    my $kidname = $myobjs{"$kid"}->name();
# kids can be subgroups or standalone monitors
    my $health = recurse("/$kidname");
    print "$health{$health} <a href=\"$rurl/$kidname\">$kidname</a><br>\n";
    $prodtest = $kid if $kidname eq "Production";
  }
  print "</p>\n";
} else {
  $extname = $pi;
  print "pi,name,extname,script: $pi,$name,$extname,$script\n" if $DEBUG;
# print where we are
  $uriname = $pi;
  $uriname =~ s#^/##;
  #print $cgi->p("name is $name");
  #print $cgi->p("uriname is $uriname");
  $uricompositepart = "/";
  @uriparts = split('/',$uriname);
  $lastpart = pop @uriparts;
  print qq(<p class="ss"><a href="$script"><b>Sitescope</b></a><br>);
  print qq(<b>Monitors in: );
  foreach $uripart (@uriparts) {
    my $healthp = recurse("$uricompositepart$uripart");
# build valid link
    ##$link = qq(<a class="good" href="$script$uricompositepart$uripart">$uripart</a>: );
    $link = qq(<a class="$healthp" href="$script$uricompositepart$uripart">$uripart</a>: );
    $uricompositepart .= "$uripart/";
    print $link;
  }
  my $healthp = recurse("$uricompositepart$lastpart");
  $color = $healthp eq "error" ? "red" : "green";
  print qq(<font color="$color">$lastpart</font></b></p>\n);
  print qq(<table border="1" cellspacing="0">);
  #print qq(<table>);
  %hashtrs = ();
  foreach $kid ($myobjs{"$extname"}->get_children()) {
    print "kid id: " . $myobjs{"$kid"}->id() . "\n" if $DEBUG;
    next unless $myobjs{"$kid"}->hasnamedkids();
    foreach $gdkid ($myobjs{"$kid"}->get_children()) {
      print "gdkid id: " . $myobjs{"$gdkid"}->id() . "\n" if $DEBUG;
      $gdkidname = $myobjs{"$gdkid"}->name();
      $gdkidextname = $myobjs{"$gdkid"}->extname();
      my $health = recurse("$gdkidextname");
      my $type = $myobjs{"$gdkid"}->type();
# dig deeper to learn health of the grankid's grandkids
      $objct = $healthct{good} = $healthct{error} = $healthct{warning} = 0;
      foreach $ggkid ($myobjs{"$gdkidextname"}->get_children()) {
        print "ggkid id: " . $myobjs{"$ggkid"}->id() . "\n" if $DEBUG;
        next unless $myobjs{"$ggkid"}->hasnamedkids();
        foreach $gggdkid ($myobjs{"$ggkid"}->get_children()) {
          print "gggdkid id: " . $myobjs{"$gggdkid"}->id() . "\n" if $DEBUG;
          $gggdkidname = $myobjs{"$gggdkid"}->name();
          $gggdkidextname = $myobjs{"$gggdkid"}->extname();
          my $health = recurse("$gggdkidextname");
          $objct++;
          $healthct{$health}++;
        }
      }
      $elemct++;
      $elemid = "elemid" . $elemct;
# groups should have distinctive cell background color to set them apart from monitors
      if ($type eq "group") {
        $bgcolor = "#F0F0F0";
        $celllink = "$lastpart/$gdkidname";
        $truncvalue = qq(<font color="red">$healthct{error}</font>/$objct);
        $tdval = $truncvalue;
      } else {
        $bgcolor = "#FFFFFF";
        $celllink = "$rprt?$gdkidname";
# truncate monitor value to save display space
        $longvalue = $monitorv{"$gdkidname"};
        (my $truncvalue) = $monitorv{"$gdkidname"} =~ /^(.{7,9})/;
        $truncvalue = $truncvalue? $truncvalue : "&nbsp;";
        $tdval = qq(<span id="$elemid" onmouseover="changeme('$elemid','$longvalue')" onmouseout="restorem
e('$elemid','$truncvalue')">$truncvalue</span>);
      }
      $hashtrs{"$gdkidname"} = qq(<tr><td bgcolor="#000000">$health{$health} </td><td>$tdval</td><td bgcol
or="$bgcolor"><a href="$celllink">$gdkidname</a></td></tr>\n);
# for health we're going to have to recurse
    }
  }
# print out in alphabetical order
  foreach $key (sort(keys %hashtrs)) {
    print $hashtrs{"$key"};
  }
  print "</table>";
}
print $cgi->end_html();
#######################################
sub recurse {
# to get the union of health of all ancestors
my $moniext = shift;
my ($moni) = $moniext =~ m#/([^/]+)$#;
# don't bother recursing and all that unless we have to...
return $myobjs{"$moniext"}->health() if defined $myobjs{"$moniext"}->health();
print "moni,moniext: $moni, $moniext\n" if $DEBUG;
my ($kid,$gdkidextname,$health,$cumhealth);
$cumhealth = $health = $monitors{"$moni"} ? $monitors{"$moni"} : "good";
foreach $kid ($myobjs{"$moniext"}->get_children()) {
    if ($myobjs{"$kid"}->hasnamedkids()) {
      foreach $gdkid ($myobjs{"$kid"}->get_children()) {
        $gdkidextname = $myobjs{"$gdkid"}->extname();
# for health we're going to have to recurse
        $health = recurse("$gdkidextname");
        if ($health eq "error" || $cumhealth eq "error") {
          $cumhealth = "error";
        } elsif ($health eq "warning" || $cumhealth eq "warning") {
          $cumhealth = "warning";
        }
      }
    } else {
# this kid is end of line
      $health = $monitors{"$kid"} ? $monitors{"$kid"} : "good";
        if ($health eq "error" || $cumhealth eq "error") {
          $cumhealth = "error";
        } elsif ($health eq "warning" || $cumhealth eq "warning") {
          $cumhealth = "warning";
        }
    }
}
$myobjs{"$moniext"}->health("$cumhealth");
return $cumhealth;
} # end sub recurse

I call it simply “ss” to minimize the typing required. You see it uses a package called Id.pm which I wrote to encapsulate the class and methods. Here is Id.pm:

package Id;
# Copyright work under the Artistic License, http://www.opensource.org/licenses/Artistic-2.0
# class for storing data about an id
# URL (not currently protected): http://localhost:8080/SiteScope/services/APIConfigurationImpl?method=getC
onfigurationSnapshot
# class for storing data about a group
use warnings;
use strict;
use Carp;
#group methods
# constructor
# get_members
# get_name
# get_id
# addmember
#
# member methods
# constructor
# get_id
# get_name
# get_type
# get_gp
# set_gp
 
sub new {
  my $class = shift;
  my $self = {@_};
  bless($self, "Id");
  return $self;
}
# get-set methods, p. 355
sub parentid { $_[0]->{parentid}=$_[1] if defined $_[1]; $_[0]->{parentid} }
sub isanamedid { $_[0]->{isanamedid}=$_[1] if defined $_[1]; $_[0]->{isanamedid} }
sub id { $_[0]->{id}=$_[1] if defined $_[1]; $_[0]->{id} }
sub name { $_[0]->{name}=$_[1] if defined $_[1]; $_[0]->{name} }
sub extname { $_[0]->{extname}=$_[1] if defined $_[1]; $_[0]->{extname} }
sub type { $_[0]->{type}=$_[1] if defined $_[1]; $_[0]->{type} }
sub health { $_[0]->{health}=$_[1] if defined $_[1]; $_[0]->{health} }
sub hasnamedkids { $_[0]->{hasnamedkids}=$_[1] if defined $_[1]; $_[0]->{hasnamedkids} }
 
# get children - use anonymous array, book p. 221-222
sub get_children {
# return empty array if arrary hasn't been defined...
  defined @{$_[0]->{children}} ? @{$_[0]->{children}} : ();
}
# adding children
sub addchild {
  $_[0]->{children} = [] unless defined  $_[0]->{children};
  push @{$_[0]->{children}},$_[1];
}
 
1;

ss also assumes the existence of just a few of the images from SiteScope classic – the green circle for good, red diamond for error and yellow warning, etc.. I borrowed them SiteScope classic.

Here is the code for the log scraper:

#!/usr/bin/perl
# analyze SiteScope log file
# Copyright work under the Artistic License, http://www.opensource.org/licenses/Artistic-2.0
# 8/2010
$DEBUG = 0;
$logdir = "/opt/SiteScope/logs";
$monitorstats = "/tmp/monitorstats.txt";
$monitorstatshis = "/tmp/monitorstats-his.txt";
$date = `date +%Y_%m_%d`;
chomp($date);
$file = "$logdir/SiteScope$date.log";
open(LOG,"$file") || die "Cannot open SiteScope log file: $file!!\n";
# example lines:
# 16:51:07 08/02/2010     good    LDAPServers     LDAP SSL test : ldapsrv.drj.com exit: 0, 0.502 sec    1:
3481  0       502
#16:51:22 08/02/2010     good    Network DNS: (AMEAST) ns2  0.033 sec   2:3459      200     33      ok
#16:51:49 08/02/2010     good    Proxy   proxy.pac script on iwww    0.055 sec   2:12467 200     55   ok
     4288    1280782309      0    0  55      0       0      200  0
#16:52:04 08/02/2010     good    Proxy   Disk Space: earth /logs   66% full, 13862MB free, 41921MB total
 3:3598      66      139862
#16:52:09 08/02/2010     good    DrjExtranet  URL: wwwsecure.drj.com     0.364 sec    1:3604      200
364  ok 26125   1280782328     0    0   358     4       2       200  0
while(<LOG>) {
  ($time,$date,$status,$group,$monitor,$value) = /(\S+)\s(\S+)\t(\S+)\t(\S+)\t([^\t]+)\t([^\t]+)/;
  print '$time,$date,$status,$group,$monitor,$value' . "$time,$date,$status,$group,$monitor,$value\n" if $DEBUG;
  next if $group =~ /__health__/; # don't care about these lines
  $mons{"$monitor"} = 1;
  push @{$mont{"$monitor"}} , $time;
  push @{$mond{"$monitor"}} , $date;
  push @{$monh{"$monitor"}} , $status;
  push @{$monv{"$monitor"}} , $value;
}
# open output at last moment to minimize chances of reading while locked for writing
open(MONITORSTATS,">$monitorstats") || die "Cannot open monitor stats file $monitorstats!!\n";
open(MONITORSTATSHIS,">$monitorstatshis") || die "Cannot open monitor stats file $monitorstatshis!!\n";
# write it all out - will always print the latest values
foreach $monitor (keys %mons) {
# dereference our anonymous arrays
  @times = @{$mont{"$monitor"}};
  @dates = @{$mond{"$monitor"}};
  @status = @{$monh{"$monitor"}};
  @value = @{$monv{"$monitor"}};
# last element is the latest measured status and value
  print MONITORSTATS "$monitor\t$status[-1]\t$value[-1]\n";
  print MONITORSTATSHIS "$monitor\n";
  #for ($i=-11;$i<0;$i++) {
# put latest measure on top
  for ($i=-1;$i>-13;$i--) {
    $time = defined $times[$i] ? $times[$i] : "NA";
    $date = defined $dates[$i] ? $dates[$i] : "NA";
    $stat = defined $status[$i] ? $status[$i] : "NA";
    $val = defined $value[$i] ? $value[$i] : "NA";
    print MONITORSTATSHIS "\t$time\t$date\t$stat\t$val\n";
  }
}

As I said it gets called every minute by cron.

That’s it! I enter the url sitescope.drj.com/SS/ss to access the main program which gets executed because I made /SS a CGI-BIN directory.

This gives you a read-only, Java-free view into your SiteScope status and hierarchy which beckons back to the good old days of Freshwater SiteScope.

Know your limits
What it does not do, unfortunately, is allow you to run a monitor – that seems like the next most simple thing which I should have been able to do but couldn’t figure out – much less define new monitors (never going to happen) or alerts.

I use this successfully against my HP SiteScope instance of roughly 400 monitors which itself is on a VM and there is no apparent strain. At some point this simple-minded script would no longer scale to suit the task at hand, but it might be good for up to a few thousand monitors.

And now a word about open source alternatives
Since I was so enamored with SiteScope Classic there seemed to be no compelling reason to shell out the dough for HP SiteScope with its unwanted interface, so I briefly looked around at free alternatives. Free sounds good, right? Not so much in practice. Out there in Cyberspace there is an enthusiast for a product called Zabbix. I just want to go on the record that Zabbix is the most confused piece of junk I have run across. You are getting less than what you paid for ($0) because you will be wasting a lot of time with it, and in the end it isn’t all that capable. Nagios also had its limits – I can’t remember the exact reason I didn’t go down that route, but there were definite reasons.

HP SiteScope is no panacea. “HP” and “stifling bureaucracy” need to be mentioned in the same sentence. Every time we renew support it is the most confusing mess of line items. Every time there’s a new cast of characters over at HP who nothing about the account’s history. You practically have to beg them to accept your money for a low-budget item like SiteScope because they really don’t pursue it in any way. Then their SAID and contract numbers stuff is confusing if you only see it once every few years.

Conclusion
A conversion program does exist for turning the finicky HP SiteScope Java-encumbered view into pure SiteScope Classic because I wrote it! But it’s a limited read-only view. Still, it’s helpful in a pinch and can even be viewed on the Blackberry’s browser.

Another problem is that HP has threatened to completely change the API so this tool, which is designed for HP SiteScope v 10.12, will probably completely break for newer versions. Oh, well.

References
This post shows some silly mistakes to avoid when doing a minor upgrade in version 11.