Re: [LARTC] how can I monitor a (dumb) switch ?

[Daniel Lopes <lopsch@lopsch.com>]

Radu CUGUT schrieb:
> Hello there,
> 
> Can anyone help me with a problem i have....
> 
> I have an ethernet LAN, made over dumb fast-ethernet switches
> (10/100mbit) without management, so there is no IP for the switches.
> 
> What I want, if possible, is to find out if a switch is down or not.
> 
> It's like with routers... if you want to find out if a router is OK,
> either you send ICMP directly to the router, or to a host "behind" the
> router.
> 
> Is there any device, or ANY OTHER possibility that I can find out if a
> switch is unplugged or broken.  Users on my LAN aren't reliable (they
> have firewalls, closed computers, etc.), so pinging users that are
> linked to a switch to find out is out of the question.
> 
> I have got an ideea that if I take an ehernet card, and somehow manage
> to put power in it, than I would have a device with MAC addres to
> arping ... is this correct ?
> 
> MANY thanks in advance, and SORRY for being a bit out of topic.
> 
> 
> Best regards,
> Radu.
> 
Ping a client you surely know should be connected to the switch. ARP 
will take the part to find out the hardware address so the packet can be 
delivered. If the switch is on it should find a hardware address and ARP 
should put it in your ARP cache. It´s independet from ICMP blocks and 
similar. So after trying to ping you should have an entry in your ARP 
table which you can control with "arp" command.

_______________________________________________
LARTC mailing list
LARTC@mailman.ds9a.nl
http://mailman.ds9a.nl/cgi-bin/mailman/listinfo/lartc