<html xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:m="http://schemas.microsoft.com/office/2004/12/omml" xmlns="http://www.w3.org/TR/REC-html40">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<meta name="Title" content="">
<meta name="Keywords" content="">
<meta name="Generator" content="Microsoft Word 15 (filtered medium)">
<style><!--
/* Font Definitions */
@font-face
        {font-family:"Cambria Math";
        panose-1:2 4 5 3 5 4 6 3 2 4;}
@font-face
        {font-family:Calibri;
        panose-1:2 15 5 2 2 2 4 3 2 4;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
        {margin:0cm;
        margin-bottom:.0001pt;
        font-size:12.0pt;
        font-family:"Times New Roman";}
h1
        {mso-style-priority:9;
        mso-style-link:"Heading 1 Char";
        margin-top:24.0pt;
        margin-right:0cm;
        margin-bottom:0cm;
        margin-left:0cm;
        margin-bottom:.0001pt;
        page-break-after:avoid;
        font-size:14.0pt;
        font-family:"Calibri Light";
        color:#2F5496;}
h2
        {mso-style-priority:9;
        mso-style-link:"Heading 2 Char";
        margin-top:10.0pt;
        margin-right:0cm;
        margin-bottom:0cm;
        margin-left:0cm;
        margin-bottom:.0001pt;
        page-break-after:avoid;
        font-size:13.0pt;
        font-family:"Calibri Light";
        color:#4472C4;}
h3
        {mso-style-priority:9;
        mso-style-link:"Heading 3 Char";
        margin-top:10.0pt;
        margin-right:0cm;
        margin-bottom:0cm;
        margin-left:0cm;
        margin-bottom:.0001pt;
        page-break-after:avoid;
        font-size:12.0pt;
        font-family:"Calibri Light";
        color:#4472C4;}
h4
        {mso-style-priority:9;
        mso-style-link:"Heading 4 Char";
        margin-top:10.0pt;
        margin-right:0cm;
        margin-bottom:0cm;
        margin-left:0cm;
        margin-bottom:.0001pt;
        page-break-after:avoid;
        font-size:12.0pt;
        font-family:"Calibri Light";
        color:#4472C4;
        font-style:italic;}
h5
        {mso-style-priority:9;
        mso-style-link:"Heading 5 Char";
        margin-top:10.0pt;
        margin-right:0cm;
        margin-bottom:0cm;
        margin-left:0cm;
        margin-bottom:.0001pt;
        page-break-after:avoid;
        font-size:12.0pt;
        font-family:"Calibri Light";
        color:#1F3763;
        font-weight:normal;}
h6
        {mso-style-priority:9;
        mso-style-link:"Heading 6 Char";
        margin-top:10.0pt;
        margin-right:0cm;
        margin-bottom:0cm;
        margin-left:0cm;
        margin-bottom:.0001pt;
        page-break-after:avoid;
        font-size:12.0pt;
        font-family:"Calibri Light";
        color:#1F3763;
        font-weight:normal;
        font-style:italic;}
p.MsoHeading7, li.MsoHeading7, div.MsoHeading7
        {mso-style-priority:9;
        mso-style-link:"Heading 7 Char";
        margin-top:10.0pt;
        margin-right:0cm;
        margin-bottom:0cm;
        margin-left:0cm;
        margin-bottom:.0001pt;
        page-break-after:avoid;
        font-size:12.0pt;
        font-family:"Calibri Light";
        color:#404040;
        font-style:italic;}
p.MsoHeading8, li.MsoHeading8, div.MsoHeading8
        {mso-style-priority:9;
        mso-style-link:"Heading 8 Char";
        margin-top:10.0pt;
        margin-right:0cm;
        margin-bottom:0cm;
        margin-left:0cm;
        margin-bottom:.0001pt;
        page-break-after:avoid;
        font-size:10.0pt;
        font-family:"Calibri Light";
        color:#4472C4;}
p.MsoHeading9, li.MsoHeading9, div.MsoHeading9
        {mso-style-priority:9;
        mso-style-link:"Heading 9 Char";
        margin-top:10.0pt;
        margin-right:0cm;
        margin-bottom:0cm;
        margin-left:0cm;
        margin-bottom:.0001pt;
        page-break-after:avoid;
        font-size:10.0pt;
        font-family:"Calibri Light";
        color:#404040;
        font-style:italic;}
p.MsoCaption, li.MsoCaption, div.MsoCaption
        {mso-style-priority:35;
        margin:0cm;
        margin-bottom:.0001pt;
        font-size:9.0pt;
        font-family:"Times New Roman";
        color:#4472C4;
        font-weight:bold;}
p.MsoTitle, li.MsoTitle, div.MsoTitle
        {mso-style-priority:10;
        mso-style-link:"Title Char";
        margin-top:0cm;
        margin-right:0cm;
        margin-bottom:15.0pt;
        margin-left:0cm;
        mso-add-space:auto;
        border:none;
        padding:0cm;
        font-size:26.0pt;
        font-family:"Calibri Light";
        color:#323E4F;
        letter-spacing:.25pt;}
p.MsoTitleCxSpFirst, li.MsoTitleCxSpFirst, div.MsoTitleCxSpFirst
        {mso-style-priority:10;
        mso-style-link:"Title Char";
        mso-style-type:export-only;
        margin:0cm;
        margin-bottom:.0001pt;
        mso-add-space:auto;
        border:none;
        padding:0cm;
        font-size:26.0pt;
        font-family:"Calibri Light";
        color:#323E4F;
        letter-spacing:.25pt;}
p.MsoTitleCxSpMiddle, li.MsoTitleCxSpMiddle, div.MsoTitleCxSpMiddle
        {mso-style-priority:10;
        mso-style-link:"Title Char";
        mso-style-type:export-only;
        margin:0cm;
        margin-bottom:.0001pt;
        mso-add-space:auto;
        border:none;
        padding:0cm;
        font-size:26.0pt;
        font-family:"Calibri Light";
        color:#323E4F;
        letter-spacing:.25pt;}
p.MsoTitleCxSpLast, li.MsoTitleCxSpLast, div.MsoTitleCxSpLast
        {mso-style-priority:10;
        mso-style-link:"Title Char";
        mso-style-type:export-only;
        margin-top:0cm;
        margin-right:0cm;
        margin-bottom:15.0pt;
        margin-left:0cm;
        mso-add-space:auto;
        border:none;
        padding:0cm;
        font-size:26.0pt;
        font-family:"Calibri Light";
        color:#323E4F;
        letter-spacing:.25pt;}
p.MsoSubtitle, li.MsoSubtitle, div.MsoSubtitle
        {mso-style-priority:11;
        mso-style-link:"Subtitle Char";
        margin:0cm;
        margin-bottom:.0001pt;
        font-size:12.0pt;
        font-family:"Calibri Light";
        color:#4472C4;
        letter-spacing:.75pt;
        font-style:italic;}
a:link, span.MsoHyperlink
        {mso-style-priority:99;
        color:blue;
        text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
        {mso-style-priority:99;
        color:purple;
        text-decoration:underline;}
p.MsoNoSpacing, li.MsoNoSpacing, div.MsoNoSpacing
        {mso-style-priority:1;
        mso-style-link:"No Spacing Char";
        margin:0cm;
        margin-bottom:.0001pt;
        font-size:10.0pt;
        font-family:"Times New Roman";}
p.MsoListParagraph, li.MsoListParagraph, div.MsoListParagraph
        {mso-style-priority:34;
        margin-top:0cm;
        margin-right:0cm;
        margin-bottom:0cm;
        margin-left:36.0pt;
        margin-bottom:.0001pt;
        mso-add-space:auto;
        font-size:12.0pt;
        font-family:"Times New Roman";}
p.MsoListParagraphCxSpFirst, li.MsoListParagraphCxSpFirst, div.MsoListParagraphCxSpFirst
        {mso-style-priority:34;
        mso-style-type:export-only;
        margin-top:0cm;
        margin-right:0cm;
        margin-bottom:0cm;
        margin-left:36.0pt;
        margin-bottom:.0001pt;
        mso-add-space:auto;
        font-size:12.0pt;
        font-family:"Times New Roman";}
p.MsoListParagraphCxSpMiddle, li.MsoListParagraphCxSpMiddle, div.MsoListParagraphCxSpMiddle
        {mso-style-priority:34;
        mso-style-type:export-only;
        margin-top:0cm;
        margin-right:0cm;
        margin-bottom:0cm;
        margin-left:36.0pt;
        margin-bottom:.0001pt;
        mso-add-space:auto;
        font-size:12.0pt;
        font-family:"Times New Roman";}
p.MsoListParagraphCxSpLast, li.MsoListParagraphCxSpLast, div.MsoListParagraphCxSpLast
        {mso-style-priority:34;
        mso-style-type:export-only;
        margin-top:0cm;
        margin-right:0cm;
        margin-bottom:0cm;
        margin-left:36.0pt;
        margin-bottom:.0001pt;
        mso-add-space:auto;
        font-size:12.0pt;
        font-family:"Times New Roman";}
p.MsoQuote, li.MsoQuote, div.MsoQuote
        {mso-style-priority:29;
        mso-style-link:"Quote Char";
        margin:0cm;
        margin-bottom:.0001pt;
        font-size:12.0pt;
        font-family:"Times New Roman";
        color:black;
        font-style:italic;}
p.MsoIntenseQuote, li.MsoIntenseQuote, div.MsoIntenseQuote
        {mso-style-priority:30;
        mso-style-link:"Intense Quote Char";
        margin-top:10.0pt;
        margin-right:46.8pt;
        margin-bottom:14.0pt;
        margin-left:46.8pt;
        border:none;
        padding:0cm;
        font-size:12.0pt;
        font-family:"Times New Roman";
        color:#4472C4;
        font-weight:bold;
        font-style:italic;}
span.MsoSubtleEmphasis
        {mso-style-priority:19;
        color:gray;
        font-style:italic;}
span.MsoIntenseEmphasis
        {mso-style-priority:21;
        color:#4472C4;
        font-weight:bold;
        font-style:italic;}
span.MsoSubtleReference
        {mso-style-priority:31;
        font-variant:small-caps;
        color:#ED7D31;
        text-decoration:underline;}
span.MsoIntenseReference
        {mso-style-priority:32;
        font-variant:small-caps;
        color:#ED7D31;
        letter-spacing:.25pt;
        font-weight:bold;
        text-decoration:underline;}
span.MsoBookTitle
        {mso-style-priority:33;
        font-variant:small-caps;
        letter-spacing:.25pt;
        font-weight:bold;}
p.MsoTocHeading, li.MsoTocHeading, div.MsoTocHeading
        {mso-style-priority:39;
        margin-top:24.0pt;
        margin-right:0cm;
        margin-bottom:0cm;
        margin-left:0cm;
        margin-bottom:.0001pt;
        page-break-after:avoid;
        font-size:14.0pt;
        font-family:"Calibri Light";
        color:#2F5496;
        font-weight:bold;}
span.Heading1Char
        {mso-style-name:"Heading 1 Char";
        mso-style-priority:9;
        mso-style-link:"Heading 1";
        font-family:"Calibri Light";
        color:#2F5496;
        font-weight:bold;}
span.Heading2Char
        {mso-style-name:"Heading 2 Char";
        mso-style-priority:9;
        mso-style-link:"Heading 2";
        font-family:"Calibri Light";
        color:#4472C4;
        font-weight:bold;}
span.Heading3Char
        {mso-style-name:"Heading 3 Char";
        mso-style-priority:9;
        mso-style-link:"Heading 3";
        font-family:"Calibri Light";
        color:#4472C4;
        font-weight:bold;}
span.Heading4Char
        {mso-style-name:"Heading 4 Char";
        mso-style-priority:9;
        mso-style-link:"Heading 4";
        font-family:"Calibri Light";
        color:#4472C4;
        font-weight:bold;
        font-style:italic;}
span.Heading5Char
        {mso-style-name:"Heading 5 Char";
        mso-style-priority:9;
        mso-style-link:"Heading 5";
        font-family:"Calibri Light";
        color:#1F3763;}
span.Heading6Char
        {mso-style-name:"Heading 6 Char";
        mso-style-priority:9;
        mso-style-link:"Heading 6";
        font-family:"Calibri Light";
        color:#1F3763;
        font-style:italic;}
span.Heading7Char
        {mso-style-name:"Heading 7 Char";
        mso-style-priority:9;
        mso-style-link:"Heading 7";
        font-family:"Calibri Light";
        color:#404040;
        font-style:italic;}
span.Heading8Char
        {mso-style-name:"Heading 8 Char";
        mso-style-priority:9;
        mso-style-link:"Heading 8";
        font-family:"Calibri Light";
        color:#4472C4;}
span.Heading9Char
        {mso-style-name:"Heading 9 Char";
        mso-style-priority:9;
        mso-style-link:"Heading 9";
        font-family:"Calibri Light";
        color:#404040;
        font-style:italic;}
span.TitleChar
        {mso-style-name:"Title Char";
        mso-style-priority:10;
        mso-style-link:Title;
        font-family:"Calibri Light";
        color:#323E4F;
        letter-spacing:.25pt;}
span.SubtitleChar
        {mso-style-name:"Subtitle Char";
        mso-style-priority:11;
        mso-style-link:Subtitle;
        font-family:"Calibri Light";
        color:#4472C4;
        letter-spacing:.75pt;
        font-style:italic;}
span.NoSpacingChar
        {mso-style-name:"No Spacing Char";
        mso-style-priority:1;
        mso-style-link:"No Spacing";}
span.QuoteChar
        {mso-style-name:"Quote Char";
        mso-style-priority:29;
        mso-style-link:Quote;
        color:black;
        font-style:italic;}
span.IntenseQuoteChar
        {mso-style-name:"Intense Quote Char";
        mso-style-priority:30;
        mso-style-link:"Intense Quote";
        color:#4472C4;
        font-weight:bold;
        font-style:italic;}
span.EmailStyle46
        {mso-style-type:personal-reply;
        font-family:Calibri;
        color:windowtext;}
span.msoIns
        {mso-style-type:export-only;
        mso-style-name:"";
        text-decoration:underline;
        color:teal;}
.MsoChpDefault
        {mso-style-type:export-only;
        font-size:10.0pt;}
@page WordSection1
        {size:595.0pt 842.0pt;
        margin:72.0pt 72.0pt 72.0pt 72.0pt;}
div.WordSection1
        {page:WordSection1;}
--></style>
</head>
<body bgcolor="white" lang="EN-US" link="blue" vlink="purple">
<div class="WordSection1">
<p class="MsoNormal" style="margin-left:36.0pt"><b><span style="font-family:Calibri;color:black">From:
</span></b><span style="font-family:Calibri;color:black">Yujun Zhang <zhangyujun+zte@gmail.com><br>
<b>Date: </b>Thursday, 12 January 2017 at 17:37<br>
<br>
</span><o:p></o:p></p>
<div>
<div>
<div>
<div>
<p class="MsoNormal" style="margin-left:36.0pt">On Thu, Jan 12, 2017 at 5:12 PM Afek, Ifat (Nokia - IL) <<a href="mailto:ifat.afek@nokia.com">ifat.afek@nokia.com</a>> wrote:<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal" style="margin-left:36.0pt"> <o:p></o:p></p>
</div>
<div>
<div>
<p class="MsoNormal" style="margin-left:36.0pt">'deduced' vs 'monitored' would be good enough for most cases. Unless we have identify some real use case, I also think there is no need for bring in quantitative indicator like counter or probability.<o:p></o:p></p>
</div>
</div>
<div>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">[Ifat] I agree.<o:p></o:p></p>
<p class="MsoNormal"> <o:p></o:p></p>
</div>
<blockquote style="border:none;border-left:solid #CCCCCC 1.0pt;padding:0cm 0cm 0cm 6.0pt;margin-left:4.8pt;margin-right:0cm">
<div>
<div>
<div>
<div>
<div>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:36.0pt">
Personally, I don’t think this is needed. I think that if Nagios reports an error, then it is confident enough without getting it from another monitor.<o:p></o:p></p>
</div>
</div>
</div>
</div>
</div>
</blockquote>
<div>
<p class="MsoNormal" style="margin-left:36.0pt"><o:p> </o:p></p>
</div>
<div>
<p class="MsoNormal" style="margin-left:36.0pt">You are right. We would consider a reported alarm as a reliable indicator of fault. What I was thinking about is: when we the alarm is not seen, can we be sure there is no fault? <o:p></o:p></p>
</div>
<div>
<p class="MsoNormal" style="margin-left:36.0pt"><o:p> </o:p></p>
</div>
<div>
<p class="MsoNormal" style="margin-left:36.0pt">Another situation is slow upstream alarm with fast downstream alarm. I don't have an actual example for the moment, so please allow me to imagine an extreme condition.<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal" style="margin-left:36.0pt"><o:p> </o:p></p>
</div>
<div>
<p class="MsoNormal" style="margin-left:36.0pt">Suppose host fault will cause instance fault. But due to some restriction, the host fault is scanned every 1 hour, but instance fault can be scanned every 1 second. Now, we get alarms from 10 instance in the same
 host. Can we deduce that the host is likely in fault status? And we may raise a "deduced" alarm on the host and trigger an immediate scan which may result in a "monitored" alarm. In this way, we reduce the time of detecting the root cause, i.e host fault.<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">[Ifat] I understand the use case.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal" style="margin-left:36.0pt"><o:p> </o:p></p>
</div>
<div>
<p class="MsoNormal" style="margin-left:36.0pt">An alternative solution is to distinguish fault from alarm. Alarm is actually a reflection of fault status.  Beside the directly linked alarm, fault status can also be deduced from downstream alarms. I haven't
 think over this model yet, it just flashed over my mind. Any comments are welcome.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">[Ifat] Isn’t ‘fault vs. alarm’ just a different terminology for ‘deduced vs. monitored’?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
</div>
</div>
</div>
</div>
</body>
</html>