What does “No More Variables Remained in this MIB View” (Linux) mean?

Question

On Ubuntu 12.04, I get a trigger to get a subtree of control values ​​with the following command:

snmpwalk -v 2c -c public localhost 

with the last line of output

 iso.3.6.1.2.1.25.1.7.0 = No more variables left in this MIB View (It is past the end of the MIB tree) 

This is mistake? A warning? Does the subtree remain?

Answer 1

Here is a little more than you might suspect. I come across this in every new Ubuntu window that I create, and I consider this a problem (not an error, but a problem - more on this later).

Here is a technically correct explanation (why this is not a “mistake”):

“There are no more variables in this MIB view” is not particularly a mistake; rather, this is an expression about your request. The request began with something simple, say “.1.3” and continued to request the “next” lexicographic OID. He received the “next” OID to the last, after which the agent informed you that nothing was visible; Do not bother with questions.

Now, this is why I consider this a problem (in the context of this question):

The "snmpd" installation point and its launch is to collect meaningful field information; Typically, this information is performance oriented. For example, three common things I need to know about are network interface information (IF-MIB :: ifHCInOctets and IF-MIB :: ifHCOutOctets), disk information (UCD-SNMP-MIB :: dskUsed and UCD-SNMP - MIB :: dskTotal) and processor information (UCD-SNMP-MIB :: ssCpuRawIdle, UCD-SNMP-MIB :: ssCpuRawWait, etc.).

The default snmpd configuration of Ubuntu specifically prohibits almost anything useful with this configuration (restricting access to enough information to tell you that the field is a Linux box):

 view systemonly included .1.3.6.1.2.1.1 view systemonly included .1.3.6.1.2.1.25.1 rocommunity public default -V systemonly 

This configuration blocks the window, which may be “safe” if it is located on an untrusted network with a little SNMP administration knowledge.

However, the first thing I do is remove the "-V systemonly" part of the "rocommunity" parameter; this will allow access to all available SNMP information (read-only) through the community string "public".

If you do this, you will probably see what you expect, these are pages and pages of SNMP information that you can use to evaluate the performance of your window.

Answer 2

In short, this is not a mistake, in fact, when you “raise” all OIDs on your agent, it will show your line> Sometimes it will not show you this line, because the last OID does not belong to your agent (you already dial all the OID from your agent, but do not view all OIDs).

Answer 3

 $ snmpwalk -v 2c -c public localhost NET-SNMP-EXTEND-MIB::nsExtendObjects NET-SNMP-EXTEND-MIB::nsExtendObjects = No more variables left in this MIB View (It is past the end of the MIB tree) 

You may also get this error while you can try to view executable scripts. I am fixing this problem to add

 view all included .1 80 

line to snmpd.conf than restarting the service

Then you will see that your output will change for both input