Getting snmpd to respond to DISMAN-PING-MIB requests

[Doug M. <dou...@gm...>]

I have recently tried to get snmpd to respond to DISMAN-PING-MIB
requests in an attempt to confirm how net-snmp implements the MIB
(since I believe that certain D-Link switches utilize net-snmp).
According to this "article," support is present but (1) limited and
(2) flat-wrong in places:
http://www.net-snmp.org/wiki/index.php/DISMAN-PING-MIB
> [1.] They are Linux only
> [2.] Rows must be created with rowStatus createAndWait before they are populated
> [3.] Agent must run as root
> [4.] Agent is blocked while tests run
> [5.] Data format for InetAddress objects is wrong. It is ASCII, not binary
>   (making it easier to use from the command line, but ...)

In any case, I have developed a set of tests to confirm functionality.

Test 1: Test for legit DISMAN-PING-MIB.
This test creates a test to the IPv4 address 1.1.1.1 in the standard way.
snmpset <authentication options> <ip of device> \
.1.3.6.1.2.1.80.1.2.1.3.6.83.101.118.79.110.101.4.116.101.115.116 i 1 \
.1.3.6.1.2.1.80.1.2.1.4.6.83.101.118.79.110.101.4.116.101.115.116 x 01010101 \
.1.3.6.1.2.1.80.1.2.1.23.6.83.101.118.79.110.101.4.116.101.115.116 i 4

Test 2: D-Link way #1.
This test is similar to the standard, except that it uses ASCII for
the IP address, even though the MIB calls for a 4-byte value.
snmpset <authentication options> <ip of device> \
.1.3.6.1.2.1.80.1.2.1.3.6.83.101.118.79.110.101.4.116.101.115.116 i 1 \
.1.3.6.1.2.1.80.1.2.1.4.6.83.101.118.79.110.101.4.116.101.115.116 s 1.1.1.1 \
.1.3.6.1.2.1.80.1.2.1.23.6.83.101.118.79.110.101.4.116.101.115.116 i 4

Test 3: D-Link way #2.
This test is identical to the previous way, except that we don't
bother to set the address type (since changing this OID is not
supported).
snmpset <authentication options> <ip of device> \
.1.3.6.1.2.1.80.1.2.1.4.6.83.101.118.79.110.101.4.116.101.115.116 s 1.1.1.1 \
.1.3.6.1.2.1.80.1.2.1.23.6.83.101.118.79.110.101.4.116.101.115.116 i 4

In my case, I have tried these tests on an snmpd daemon from net-snmp
5.4.3 (stock gentoo, stock ubuntu) and 5.7 (source on gentoo).
However, I have not been able to make them work.

I get the following error for _any_ of the OIDs that I attempt to set:
Error in packet.
Reason: notWritable (That object does not support modification)

This leads me to believe that
(1) the write string is set up correctly, since the error is _not_ "noAccess";
(2) the agent knows _something_ about the MIB, since it didn't time
out or flat-out deny me.

Has anyone made snmpd perform remote pings recently via "snmpset"?