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39

There seems to be a little confusion... you are asking about ARP tables, and you're using OID .1.3.6.1.2.1.17.4.3.1.2; however, that OID actually is for the mac-address table in the switch. I am assuming you know how to login to your Ubuntu server, and that NET-SNMP is installed... please let me know if you need pointers for doing this (see this question for ...


21

If SNMPv3 is not an option you can do some things to help secure SNMPv2 better. Don't enable the Read-Write string. There are very few reasons to enabled it. Choose community strings that are more complex and remove any that are 'private' or 'public'. Use an access-list on the community string to restrict what IP addresses can poll the device. Do not enable ...


16

Poll ifHCInUcastPkts, ifHCOutUcastPkts, ifHCInOctets and ifHCOutOctets on Vlan100, Vlan101, and Vlan102. You can find the ifIndex of these SVIs by walking ifName This get me another question : Why this difference in the same interface (VLAN-100 and Vl100) ?? VLAN-100 is a virtual interface for the actual layer2 vlan; there is no IP address associated ...


15

There are a few examples that can do this. Cacti is one. It has a weather-map plugin that can be leveraged to produce output such as the following GigaPop Illinois Wisconsin University These are examples of what the weather map plugin can do. When configured correctly you can see minute, hourly, daily, weekly and monthly traffic stats. You can download ...


15

SNMPv2u is a user-based security model, as specified in RFC 1909 and RFC 1910. SNMPv2c is a common community-based security model. SNMP 2u offers per-user authentication, similar to SNMPv3. SNMPv2u never really took off in the wild; anyone who wants per-user authentication uses SNMPv3. For more details (and there are a lot), consider this article in the ...


14

SNMPv2 should not be used especially if SNMPv3 is available. There are some basic flaws in SNMPv2, predominantly the use of community strings which are sent over the network in an unencrypted form to query the network infrastructure. Also it's based on a community string instead of a separate username/password combination, SNMPv2 (and 1 for that matter) ...


12

Yes, this data is populated in the Firewall MIB .1.3.6.1.4.1.2636.3.5.2.1.5 contains your counters .1.3.6.1.4.1.2636.3.5.2.1.6 contains your filter names .1.3.6.1.4.1.2636.3.5.2.1.7 contains your counter names show firewall filter RE-FILTER | match mgmt_ntp mgmt_ntp 199728 2628 % snmpbulkwalk jnpr .1.3.6.1.4.1.2636.3.5.2.1.7|grep ...


12

I think that you have another switch or hub connected to port 24 of your 2960, and there are 4 hosts connected to that switch/hub.


10

Try adding the counter command under the SVI (see here for more information, specifically the "Understanding L3 interface counters" section). For instance: Cisco#config t Cisco(config)#interface vlan 100 Cisco(config-if)#counter ? ipv4 Enable IPv4 statistic counters ipv6 Enable IPv6 statistic counters <cr> Cisco(config-if)#counter ...


10

Private MIBs are usually vendor specific. They contain additional information for their specific equiment which cannot be provided through RFC-defined MIBs. This way the vendor can provide more information. To answer your second question: sometimes vendors provide both: the RFC-defined MIB contains all that can be contained there (so most software using ...


9

Whereas SNMPv3 is significantly more secure than v2, you can at least mitigate some of the risk of implementing v2 by restricting access with an ACL. I would also advise against creating a read/write v2 community.


9

Have you tried walking the MIB/OIDs in question from a management station? After having spent a lot of time w/firmware QA, I've noticed things like show commands are likely to not display correct info, even when the OIDs are poll-able. I recommend using and knowing Net-SNMP tools and utils as debug before trying to poll the information in cacti, observium, ...


9

As far as I know data you want is not available on SNMP. 3750#sh mls qos interface FastEthernet0/1 statistics ... output queues dropped: queue: threshold1 threshold2 threshold3 ----------------------------------------- queue 0: 0 0 0 queue 1: 100989 0 0 queue 2: 0 0 ...


9

I think your issue is coming from a simple misconception of how SNMP data (OIDs) is structured, and how snmpwalk, snmpget, and snmpgetnext interact with it. SNMP organizes the OIDs into related nested trees (or tables), the MIBs define those trees and the OIDs in them. It's important to understand how snmpget and snmpgetnext works before getting into ...


9

The MIB is the entire catalog of OIDs (for a particular device). An OID is a specific reference to an individual item within the MIB. An analogy: The MIB is like the phone book for my city. The OID is like my name in the phone book.


8

You're partially right in that Syslog and SNMP Traping do serve similar functions, however there are some fundamental differences. (Based on your commands/tags on the quesiton, I assume you're asking specifically about their function on a Cisco Router/Switch.) SNMP serves three main functions as you mentioned: Gathering of information with snmpget, ...


8

my own solution comes out in the form of iso.3.6.1.2.1.17.4.3.1.2.0.20.42.49.139.235 25 ... do the other numbers represent a MAC address and if so, why are they different from the give solution? First, I apologize for not including this dependency... The MIB tables you're polling are indexed by a value. In this case, you're polling ...


8

Why can't I see MAC addresses of the attached PCs on polling the OID for the above switch? When you poll 1.3.6.1.2.1.4.22.1.2, you're polling ipNetToMediaPhysAddress, which is the ARP table of the switch. Pure Layer2 switches do not have a large ARP table because they are merely switching instead of routing. Switching does not require an ARP table. ...


8

I don't believe there is a way to directly poll the results of the OR via SNMP, but you can certainly poll for the IP SLA results and calculate it yourself. Using the CISCO-RTTMON-MIB (1.3.6.1.4.1.9.9.42), you can check the timeout value of your reachability checks, take the true/false value it returns and do the OR in whatever scripting language you're ...


8

Interfaces/IP Addressing: If you're looking to poll a device's IP address, subnet mask and corresponding interface you can use the following OIDs from the IP-MIB and IF-MIB MIBs: .1.3.6.1.2.1.4.20.1.1 - The IP address can be found at this OID ~]$ snmptranslate .1.3.6.1.2.1.4.20.1.1 IP-MIB::ipAdEntAddr ~]$ snmpwalk -v2c -c cisco 10.30.46.1 .1.3.6.1.2.1.4....


7

Cisco IOS padded the last 8-bits because you apparently left a digit off to make it a legitimate value... 31 characters isn't a valid hex number [mpenning@some_machine ~]$ python Python 2.6.6 (r266:84292, Feb 22 2013, 00:00:18) [GCC 4.4.7 20120313 (Red Hat 4.4.7-3)] on linux2 Type "help", "copyright", "credits" or "license" for more information. >>>...


7

I would take a look at this support document from Cisco. In part it recommends to run the following command to see which OID's were recently polled: show snmp stats oid This gives a readout for which OID's you are polling. It will allow you to see, by judging the time stamps, which OID is taking a long time to poll. This is usually where your problem ...


7

Wow, this question could be an entire site of its own. Regardless of what software package(s) you end up using, if snmp is how you're getting your numbers, it's time to embrace sFlow (aka: NetFlow depending on your hardware). I love snmp. It's perfect for getting a plethora of network (and other) statistics. That said, if you want a deeper look into your ...


7

Have you taken a look at the ipRouteTable OID in the RFC1213-MIB? (OID number 1.3.6.1.2.1.4.21) I utilize this to pull the routing table out of several devices. It is referenced by RFC 1213 which, on page 33, gives the following information: -- The IP routing table contains an entry for each route -- presently known to this entity. ...


7

Could someone please tell me the community string indexing for switches other than Cisco? Edit: This is how to poll Q-BRIDGE-MIB for mac-addresses from the only non-Cisco I have, a DLink DGS-3200. I'm not using [community@vlan] for non-Cisco switches. You're correct that this indexing only applies to Ciscos. I expect any non-Cisco switch, which supports ...


7

Private MIBs refer to MIBs associated with a specific Private Enterprise Number which starts at the following prefix: iso.org.dod.internet.private.enterprise (1.3.6.1.4.1) These numbers are assigned by IANA and are a namespace for an organization to store their custom OIDs/MIBs. You can see the full list of PENs here. For example, all of Cicso's proprietary ...


6

Cacti is a good open source solution. You will need some Linux experience to get up and running. PRTG is a nice solution, can't be the price. You can use SNMP to monitor interfaces and it now also includes Netflow. Probably not the most robust reporting, but a good starting point for the price. SolarWinds is another huge player. Great features and ...


6

They keep moving things into the web interface but the reports are in a separate app called "Report Writer" on the server desktop so you'll have to RDP or physically connect to the server to get to it. There's also a "Report Scheduler" where you'll need add the reports once you've created them. I've never found their reporting very useful but you may have ...


6

I just tried this on my CPE: [ytti@lintukoto ~]% cat moi2.sh #!/bin/sh snmp="snmpset -v2c -cfoo bu.ip.fi" $snmp 1.3.6.1.4.1.9.9.96.1.1.1.1.2.9 i 4 \ 1.3.6.1.4.1.9.9.96.1.1.1.1.3.9 i 4 \ 1.3.6.1.4.1.9.9.96.1.1.1.1.4.9 i 1 \ 1.3.6.1.4.1.9.9.96.1.1.1.1.5.9 a 91.198.120.2 \ 1.3.6.1.4.1.9.9.96.1.1.1.1.6.9 s filename \ 1.3.6.1.4.1....


6

Is a broadcast ping to the subnet from the SVI on the switch (which is low-bandwidth), and using show mac address-table dynamic out of the question? some-switch#show mac address-table dynamic Mac Address Table ------------------------------------------- Vlan Mac Address Type Ports ---- ----------- -------- ----- 1 ...


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