The Alzheimer’s unit had 8′ drop ceilings, and there were usually flies on the ceiling [classy joint].  So, I’d fill up a cup with water and add a little detergent.  Alice and I would walk up and down the long main hall, and when I saw a fly on the ceiling I’d lift the cup up slowly under the fly, and the fly would drop into the cup, get trapped by the detergent, and squirm to death.  I’d hold the cup down for Alice to watch, and she got a kick out of it.  We spent hours walking up and down that hall, holding hands and catching flies [the other residents decided to sleep].  It was the easiest way to keep her calm.

This weekend, my sleeping schedule got screwed up, and at midnight I ended up grabbing a book of the shelf for a good re-read.  The book is “God Bless You, Mr. Rosewater,” by Kurt Vonnegut Jr., of course, and I hadn’t read it since high school.  Plugging along, I got to page 78:

“The tumbler-and-soapsuds techniqe worked like this:  A woman would look for a fly hanging upside down.  She would then bring her tumbler of suds directly under the fly very slowly, taking advantage of the fact that an upside-down fly, when approached by danger, will drop striaght down two inches or more, in a free fall, before using his wings.  Ideally, the fly would not sense danger until it was directly below him, and he would obligingly drop into the suds to be caught, to work his way down through the bubbles, to drown.”

“Of this technique Eliot often said: ‘Nobody believes it until she tries it.  Once she finds out it works, she never wants to quit.’”

So that’s where I picked that up!  What an unexpected surprise!  Nostalgia …. catching flies with Alice……

Alice’s doctor played around with her medication, and there was about a two week period where Alice was lucid and could remember my name.  “Alice, do you know my name?”  “Jason,” and she’d smile like she was a six-year-old who just got a new bicycle.  Then she went downhill and ended up in the hospital.  I went to visit her every day, but she was near death and couldn’t even open her eyes.  The nurses put a respirator mask over her mouth, to keep out the flies.  She died pretty shortly after entering the hospital.

How strange that as I approach 40, one of my fondest memories is the hours spent with a 70-year-old woman with dementia, who couldn’t remember my name, walking up and down the hall, holding hands, catching flies in a cup of dishwater…..

find /some/directory -type f -ctime +2 -name \*.txt -exec rm -f '{}' \;

On Windows, it’s ridiculously complicated.  Here’s a PowerShell script, modified from somewhere….:

$a = Get-ChildItem 'C:\Temp\subdir\*' -include *.txt
if ($a.count -gt 1) {
    foreach($x in $a) {
        $y = ((Get-Date) - $x.CreationTime).Days
        if ($y -gt 7 -and $x.PsISContainer -ne $True) {
            #$x.Delete()  #uncomment here to delete
            Write-Host $x
        }
    }
}

2) When I see an ad for 5hourenergydrink.com, I think of RFC 1123 (http://www.faqs.org/rfcs/rfc1123.html).  Does that make me some sort of geek?

“The syntax of a legal Internet host name was specified in RFC-952 [DNS:4].  One aspect of host name syntax is hereby changed: the restriction on the first character is relaxed to allow either a       letter or a digit.  Host software MUST support this more liberal syntax.”  And 3com rejoiced.

3) In tuxedo pants, there’s a hole in the top of the pockets so you can pull down your shirt to unwrinkle it.  Why don’t they have those in other pants/jeans?  It’s mighty convenient.

4) You never see Frequently Unasked Questions.

Relevant links

• Why DNS Based Global Server Load Balancing (GSLB) Doesnt Work
• Overview of DNS Caching In Browsers – Addendum to Why DNS Based GSLB Doesnt Work
• ‘Re CVS cvs.openbsd.org src’ – MARC
• Bug#340514 marked as done (libc6 dns resolver sort ip address list)
• DNS Round Robin and Destination IP address selection – Microsoft Enterprise Networking Team – Site Home – TechNet Blogs
• DNS Shuffle Records and Round-Robin (DNS RR) Chapter 12. Designing for High Availability Integrated cisco and unix network architectures Networking eTutorials.org
• FGA The uselessness of Round Robin resource record set shuffling
• djbdns – How to balance load among many web servers
• Re [TLS] Server Name Indication (SNI) in an IPv6 world
• resolv.conf(5) resolver config file – Linux man page
• test the round robin DNS features of the resolver functions » KutuKupret
• What is DNS round robin and subnet prioritization
• Windows Vista and Windows Server 2008 DNS clients do not honor DNS round robin by default
• Mark Minasi’s Reader Forum – DNS resolution order
• Mark Minasi’s Reader Forum – Name Resolution Order
• DNS balancing
• BIND’s rrset-order statement
• How Internet Explorer uses the cache for DNS host entries
• How to Disable Client-Side DNS Caching in Windows XP and Windows Server 2003
• BIND 9.4 Manual – Load Balancing

Miscellany.  Overview diagram in Visio and PNG.  adzapper postmatch.  squid examples to redirect based on source IP.  squid tee.  Wiki squid/adzapper template.  Wiki template for Java client config file (you’d be surprised how many people don’t know about it…).

Protocol Diagrams (packet diagrams): use the LaTeX bytefield package.  It’s easy.

Sequence Diagrams: use Mscgen.  Easier than Graphviz on this.

Graphs (general): use Graphviz. And the Perl module generally makes life easier.

State Diagrams: use Graphviz, or Tikz.  Tikz is intimidating, but state diagrams are simple enough.

General drawing: try Inkscape, and don’t forget OpenClipArt.org.

Windows Server 2008 R2 Service Pack 1 is being released to the masses today, and the graphics improvements Microsoft picked up when they bought Calista are now released as RemoteFX.  This RDP 7.1 update should provide better display performance for those forced by a cruel and uncaring universe to make Adobe Flash available over RDP over broadband.  One hopes.

The most effective course of action remains to block Flash advertisements at the proxy server (squid + adzapper, or Privoxy), and require the user to enable Flash when needed.  If the Flash file (.swf, say) is blocked, multiply all your performance hits by 0 — there’s nothing to transfer or optimize.  Block all the junk you don’t need.

Notes…..

IE7Pro has worked well on 2003, but it doesn’t work properly on 2008R2, and development is closed (and stagnated?).  It shouldn’t be so difficult….

Globally Disable and Enable Flash

Toggle Flash is an IE plug-in that toggles Flash (clear enough).

Changing a registry entry is all that’s required to enable and disable Flash. (see below)

Possibly, on terminal server login, disable Flash.  User must explicitly re-enable it.

Powershell (scripting out loud….)

<# flashwatch.ps1
Enable flash.  Hang around a while and after 15 minutes or so, keep an eye on Internet Explorer.  
If IE isn't running, disable Flash again.todo: make sure only one copy of this script is running
per user.#>

function flash-disable {
 $RegKey ="HKCU:\Software\Microsoft\Windows\CurrentVersion\Ext\Settings\{D27CDB6E-AE6D-11CF-96B8-444553540000}"
 Set-ItemProperty -path $RegKey -name Flags -value 1
}

function flash-enable {
 $RegKey ="HKCU:\Software\Microsoft\Windows\CurrentVersion\Ext\Settings\{D27CDB6E-AE6D-11CF-96B8-444553540000}"
 Set-ItemProperty -path $RegKey -name Flags -value 0
}

flash-enable
sleep -s 900

$keeprunning = $true
while ($keeprunning) {
 if ((Get-Process "iexplore" -ea SilentlyContinue) -eq $Null){
   flash-disable
   $keeprunning = $false
 }
 else {
   sleep -s 60
 }
}

A timestamp would be better.  Enable -> write timestamp.  Have periodic job check if time is expired (New-Timespan), and disable Flash after. Powershell is awkward.  It’s odd when Perl is easier….

Limit Flash to Specific Domains

IE 8 – per-site ActiveX Control

Per-Site ActiveX Controls
http://msdn.microsoft.com/en-us/library/dd433050%28VS.85%29.aspx

How to Disable Adobe Flash Animations for All but White-Listed Sites in Internet Explorer 8
http://www.winhelponline.com/blog/disable-flash-all-but-whitelist-sites-ie8/

regedit /s flash_allow.reg

[flash_allow.reg]
Windows Registry Editor Version 5.00
[HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Ext\Stats\{D27CDB6E-AE6D-11CF-96B8-444553540000}\iexplore\AllowedDomains\youtube.com]

The user can just say “run on all sites” so you may have to regularly remove
[HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Ext\Stats\{D27CDB6E-AE6D-11CF-96B8-444553540000}\iexplore\AllowedDomains\*]

Problems with Per-Site ActiveX Controls

• Annoying information bar which is IMPOSSIBLE TO SHUT UP.
• User can just add all sites.
• Setting is per-user setting, so it’s a PIA to restrict to specific machines (GP loopback).

IE 9 – ActiveX Filtering

IE 9 (currently at RC) is set to include ActiveX Filtering, enabling you to restrict ActiveX controls to certain domains.  But it’s apparently global. You can restrict or allow all ActiveX controls on certain sites, but you can’t restrict individual controls.  It would be desirable to be able to restrict the Flash plug-in to youtube.com, or to restrict AlternaTIFF to designated sites.  Being able to specify these per machine would be better yet.  This looks passably adequate.

About ActiveX Filtering

“Sites you have not approved cannot run these controls, and the browser will not show prominent notifications prompting you to install or enable them.”  Hallelujah, Brother.

How To Manage Your Internet Explorer 9 ActiveX Filtering Exceptions

For example, here’s the output for “perl -T rfcmap.pl RFC0821 RFC0822 RFC1035″ which covers some of the initial documents on SMTP, mail message format, and domain  names.

Could be better; could be worse.

# Copyright (c) 2011 Jason Filley jason@snakelegs.org
#
# Permission to use, copy, modify, and distribute this software for any
# purpose with or without fee is hereby granted, provided that the above
# copyright notice and this permission notice appear in all copies.
#
# THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
# WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
# MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
# ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
# WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
# ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
# OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
#
# Name: rfcmap.pl
# Purpose: Output Graphviz .dot format for dated graph of specified RFC's, plus
#   documents obsoleting or obsoleted by it/them.
# Input file:  ftp://ftp.rfc-editor.org/in-notes/rfc-ref.txt
# Usage example:  perl -T rfcmap.pl RFC1035 RFC0821 RFC0822 > output.dot
#   arguments are names of documents from first column, as written

use strict;
use warnings;
use 5.010;

if ( $#ARGV < 0 ) {
    die "Specify the RFC's to use as command-line parameters\n";
}

sub stripwhitespace {
    my $string = shift;
    $string =~ s/[\n\r\s]+//g;
    return $string;
}

sub trim {
    my $a = shift;
    $a =~ s/^[\n\r\s]+//g;
    $a =~ s/[\n\r\s]+$//g;
    return $a;
}

sub grabyear {
    my $year = shift;
    $year =~ /(\d{4})\.$/;
    return $1;
}

sub uniq {
    my %h;
    return grep { !$h{$_}++ } @_;
}

sub GetTitleOnly {
    my $title = shift;
    $title =~ /([A-Za-z]*)(0*)(\d*)/;
    my $toreturn = $1 . " " . $3;
    return $toreturn;
}

sub GetFullTitle {
    my $title = shift;
    $title =~ /(\"(.*)\\\")/;
    my $toreturn = $2;
    return $toreturn;
}

my @lines   = ();
my @todo    = ();
my @done    = ();
my @final   = ();
my %srcHoA  = ();
my %srcbib  = ();
my %srcdate = ();

push( @todo, @ARGV );
@todo = uniq(@todo);

my $file = "rfc-ref.txt";

open( RFCREF, "<$file" ) || die "Can't open file.\n";
while (<RFCREF>) {
    if (/^RFC/) {
        push( @lines, $_ );
    }
}
close(RFCREF);

# link all references
while ( scalar(@todo) > 0 ) {
    my $item = shift(@todo);
    foreach my $entry (@lines) {
        my @line = split( '\|', $entry );
        my $RFC = stripwhitespace( $line[0] );

        #hash of arrays (RFC -> @ObsoletedByList)
        my $ObsoletedBy = stripwhitespace( $line[1] );
        my @ObsoletedByList = split( ',', $ObsoletedBy );
        $srcHoA{$RFC} = [@ObsoletedByList];

        #hash (RFC -> Bib)
        my $Bib = $line[2];
        chomp $Bib;
        $Bib = trim($Bib);
        $Bib =~ s/(\")/\\$1/g;
        $srcbib{$RFC} = $Bib;

        #hash (RFC -> date)
        my @working = ();
        push( @working, $RFC );
        push( @working, @ObsoletedByList );

        if ( $item ~~ @working ) {
            unless ( $entry ~~ @final ) {
                push( @final, $entry );    #only if not already in @final
                $srcdate{$RFC} = grabyear($Bib);
            }

            foreach my $workitem (@working) {
                unless ( ( $workitem ~~ @done ) || ( $workitem ~~ @todo ) ) {
                    push( @todo, $workitem );
                }
            }
        }
    }
    @todo = grep { $_ ne $item } @todo;
    push( @done, $item );
}

# find lowest to highest quoted years (e.g., 1981..2010)
# todo: what if only one year?
my $highest_val = ( sort { $b <=> $a } values %srcdate )[0];
my $lowest_val  = ( sort { $a <=> $b } values %srcdate )[0];
my @dates = ( $lowest_val .. $highest_val );

# draw the graph
# A: Because I didn't have the time to figure out why the Graphviz perl module
# kept munging my ranks....
print
"digraph test { graph [ratio=fill, fontsize=24];\nnode [label=\"\\N\", fontsize=24];\n";

my $yearnodes;
my $yearedges;    #what if only one?

#draw the years
for ( my $count = 0 ; $count <= $#dates ; $count++ ) {
    $yearnodes .=
      $dates[$count] . " [label=" . $dates[$count] . ", shape=plaintext];\n";
    unless ( $count == 0 ) {
        $yearedges .=
            $dates[ $count - 1 ] . " -> "
          . $dates[$count]
          . " [style=dotted, shape=none];\n";
    }
}

print $yearnodes;
print $yearedges;

# draw the bib nodes
foreach my $rfcnode (@done) {
    if ( $rfcnode =~ /^RFC/ ) {

        print $rfcnode
          . " [label = \""
          . GetTitleOnly($rfcnode) . "\\n"
          . GetFullTitle( $srcbib{$rfcnode} )
          . "\" shape=plaintext, style=filled, color=lightskyblue];\n";
    }
    else {
        print $rfcnode
          . " [label = \""
          . GetTitleOnly($rfcnode)
          . "\" shape=box, style=filled, color=mediumorchid];\n";
    }
}

# set ranks
foreach my $srcnode (@done) {
    if ( $srcnode =~ /^RFC/ ) {
        print "{rank=same; " . $srcnode . " " . $srcdate{$srcnode} . ";}\n";
    }
}

# draw the edges
foreach my $srcnode (@done) {
    if ( $srcnode =~ /^RFC/ ) {
        if ( @{ $srcHoA{$srcnode} } ) {
            foreach my $ref ( @{ $srcHoA{$srcnode} } ) {
                print $srcnode . " -> " . $ref . ";\n";
            }
        }
    }
}

#close the graph
print "}\n"