Re: One more niewbie question,

shahin shahini · ‎09-25-2013

Hello,

We have an catalyst switch at our data center and we did enable the snmp on this switch and use Cacti to get an grafic chart from the switch, here is what I dont understand,

The port one of this switch is connected to the datacenter switch, we have connected 3 different machines (our firewall, UPS, etc) to 3 ports of this switch each of these machines have a public IP in the same IP reng as the data center switch, now when I look at the grafic chart I can see the total inbound and outbound on these ports, If I understood it coreclty now, the total of the inboud of the 3 ports would be the outbond of the port 1 and the total outbond of these 3 ports would be the inbound of port one. but it is not so.

data in the past 24 hours:

port1:

inbound: 6.29 GB

outbound: 58.6 GB.

port 7:

inbound: 9.97 GB

outbound: 3.86

port 11:

inbound: 50.58 GB

outbound: 4.98 GB

port 20:

inbound: 6.36 GB

outbound: 800 MB

As you can see the inbound and outbound of port on is not the total of inbound or outbound of other 4 ports.

do I missing something here?

Thanks

Joseph W. Doherty · ‎09-25-2013

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Posting

Difficult to say what the issue is. If everything is exactly as you describe, there might be an issue with the data SNMP is providing. However, are you sure everything is exactly as you describe?

When I total all your ingress and egress stats, there's about 5 GB difference.

There are no other interfaces?

There are no ACLs (they might drop packets)?

You're sure you're polling the correct OIDs for the interfaces?

Have you also done a manual show interfaces, 24 hours apart, and manually computed usage?

shahin shahini · ‎09-25-2013

Thanks for your replay,

then my understanding regarding inbond and outbond is correct, right?

I sned you an attachment, with in it an screenshot of all the ports on this switch maybe you can see somthing there. regarding your questions I have to tell you that we didnot configure the snmp manager at our end, as i siad this switch is in a data center and we did only enable the smtp on switch from the web page of the switch, forward a public IP address in our firewall to this switch, give this IP to the data center and they create this grafic for us.

1. There are no other interfaces? which interface are we talking here?

There are no ACLs (they might drop packets)? I dont think so becuse this is for the first time we did enable the snmp on this switch.

I am sorry but I cannot answer your last 2 questions.

Thanks

Joseph W. Doherty · ‎09-25-2013

Disclaimer

The Author of this posting offers the information contained within this posting without consideration and with the reader's understanding that there's no implied or expressed suitability or fitness for any purpose. Information provided is for informational purposes only and should not be construed as rendering professional advice of any kind. Usage of this posting's information is solely at reader's own risk.

Liability Disclaimer

In no event shall Author be liable for any damages whatsoever (including, without limitation, damages for loss of use, data or profit) arising out of the use or inability to use the posting's information even if Author has been advised of the possibility of such damage.

Posting

then my understanding regarding inbond and outbond is correct, right?

Yes, one interface's ingress should count as another interface's egress unless something like ACLs are dropping packets.

shahin shahini · ‎09-26-2013

Hi,

Thanks for the update,

I did run the sh access-lists and it came back with any result so I think there is no access list.

The only thing that I found out is that port 10 of this switch connect it to an other switch, but as you can see there is no trafic on this port.

Thanks