What you say about being "normal" doesn't sound quite right............

I got this from an HP forum:

**************

ifPromiscuousMode OBJECT-TYPE
SYNTAX TruthValue
MAX-ACCESS read-write
STATUS current
DESCRIPTION
"This object has a value of false(2) if this interface only
accepts packets/frames that are addressed to this station.
This object has a value of true(1) when the station accepts
all packets/frames transmitted on the media. The value
true(1) is only legal on certain types of media. If legal,
setting this object to a value of true(1) may require the
interface to be reset before becoming effective.

The value of ifPromiscuousMode does not affect the reception
of broadcast and multicast packets/frames by the interface."

****************

I don't think its normal for a switch to be this way.  Its normal for a hub
to be that way.

The above description seems right - " if this interface only accepts
packets/frames that are addressed to this station"
The part about accepting multicast and broadcast packets/frames sound like
what you mean.

However, only traffic meant for that port should be forwarded to the end
hosts. (But I guess it has to accept all to filter)

I just checked about the SNMP v1 and V2 probes.  Only the v2 probes are
reporting this.  Is it possible that Intermapper has a little bug and got
the true/false state backwards somewhere along the line????

This fits with the description from HP.

I can't imagine that a switch should ever be in promiscuous mode unless it
is a mirror port for monitoring/sniffing.  And then it would usually be only
one port - the port accepting monitoring.  All switches with the SNMP v2
probe are now reporting promiscuous mode on every interface.

Anybody else out there see this warning in red: Promiscuous Mode Enabled
??????  This only shows on the interface status page - not the device status
page.

I will have to try and walk this mib and see.

I think what you said and what the HP guys said is so close to being the
same but not quite.  You say that a switch must accept all packets as normal
(true) whereas the HP guys seem to say that only packets addressed to the
port (false) is normal.

With the replies from both of you I can now see that Cisco devices also
report the same.  This would indicate that either you are right about what
is "normal" or that Intermapper has it backwards as it happens on different
vendors eqpt and is not likely a vendor SNMP issue.

This didn't show before.  We are on ver 4.5.5.  With the red lettering I
think I would have noticed this so I feel it's a recent change.  I look at
interface status all the time.  I'll be copying your reply to HP for their
opinion.

Thanks for the response but I think we need a bit more investigation on
this.

Kevin

-----Original Message-----
From: [email protected]
[mailto:[EMAIL PROTECTED] On Behalf Of William W. Fisher
Sent: 29-Apr-07 19:27
To: InterMapper Discussion
Subject: Re: [IM-Talk] Intermapper Shows "Promiscuous Mode Enabled"

Kevin Wigle wrote:
> Just today I noticed on an HP 2824 with the SNMP probe, on each port
> Intermapper shows "Promiscuous Mode Enabled" in red in the "Other Info"
> field on the status page.
> 
> There is another 2824 directly connected to this one and it does not show
> this info.

Is the other 2824 switch being probed using SNMPv1?  InterMapper only checks
the "ifPromiscuousMode" variable when
probing a device with SNMPv2c or SNMPv3, so you will never see the
promiscuous mode warning when probing with SNMPv1.

ifPromiscuousMode "has a value of true(1) when the station accepts all
packets/frames transmitted on the media."

For the interfaces on a switch, this is the normal mode of operation. A
switch needs to receive all packets on its
interfaces so it can forward them if necessary. For interfaces on a server
or router, an interface would only be in
promiscuous mode if it was running packet sniffing software.

> Being in red must mean that Intermapper wants me to be aware.

I have filed an ER to have this removed when the device is known to be
switch. It's normal for a switch to have
interfaces in promiscuous mode.

Regards,

Bill Fisher
Dartware, LLC

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