SNMP not returning OIDs for voltage and temperature?

I have several RB450Gs and a couple of RB493Gs.

I have noticed on 3 of the RB450Gs, 2 running 4.16 and one running 4.17 and one RB493G running 4.17 that sometimes, they do not want to return the values for the temperature and / or voltage OIDs.

> snmpwalk -v1 -c community {RB493G_HOSTNAME} 1.3.6.1.4.1.14988.1.1.3
SNMPv2-SMI::enterprises.14988.1.1.3.9.0 = STRING: "n/a"
SNMPv2-SMI::enterprises.14988.1.1.3.10.0 = INTEGER: 520
> snmpwalk -v1 -c community {RB493G_HOSTNAME} 1.3.6.1.4.1.14988.1.1.3
SNMPv2-SMI::enterprises.14988.1.1.3.8.0 = INTEGER: 251
SNMPv2-SMI::enterprises.14988.1.1.3.9.0 = STRING: "n/a"
SNMPv2-SMI::enterprises.14988.1.1.3.10.0 = INTEGER: 520

I just installed the above box and tried to use mrtg’s cfgmaker with a custom host template to build the inital .cfg for that host.
I was surprised to not have entries for voltage or temperature. The first SNMP walk above was the first snmpwalk that had ever been performed against that box.

It seems like a SNMP walk is enough to kick it back into gear for a while and MRTG’s SNMP gets work again.

Two of the 450Gs have been in production for a while and occasionally stop answering for those oids. I left it alone for three days. MRTG didn’t get a good read during that time. I ran snmpwalk and the next MRTG run got good answers. I have not seen a problem with CPU utilization OIDs or the interface OIDs.

host.template snippet:

my $temp1_oid = oid_pick($router_connect,$v3opt,".1.3.6.1.4.1.14988.1.1.3.10.0");
my $temp2_oid = oid_pick($router_connect,$v3opt,".1.3.6.1.4.1.14988.1.1.3.11.0");
if ($temp1_oid){
  my $target_name = $router_name . ".temperature";
  if (! $temp2_oid) {
     $temp2_oid = "PseudoZero";
  } 
  my $dir = '';
  $dir = "Directory[$target_name]: $directory_name" if $directory_name;
  $target_lines .= <<ECHO;

$dir
Target[$target_name]: $temp1_oid&$temp2_oid:$router_connect / 10
YLegend[$target_name]: Temp C
ShortLegend[$target_name]: C
Legend1[$target_name]: Temp
Legend3[$target_name]: Max Observed Temp
LegendI[$target_name]: &nbsp;Temp :
WithPeak[$target_name]: ywm
MaxBytes[$target_name]: 100
Options[$target_name]: gauge, nopercent, noo
Title[$target_name]: $sysname Temperature
PageTop[$target_name]: <h1>$sysname Temperature</h1>
 <div><table>
 <tr><td>System:</td>     <td>$sysname in $html_syslocation</td></tr>
 <tr><td>Maintainer:</td> <td>$html_syscontact</td></tr>
 <tr><td>Description:</td><td>$html_sysdescr</td></tr>
 <tr><td>Resource:</td>   <td>Temp ($temp1_oid)</td></tr>
 </table></div>

ECHO
}

my $volt1_oid = oid_pick($router_connect,$v3opt,".1.3.6.1.4.1.14988.1.1.3.8.0");
if ($volt1_oid){
  my $target_name = $router_name . ".voltage";
  my $dir = '';
  $dir = "Directory[$target_name]: $directory_name" if $directory_name;
  $target_lines .= <<ECHO;

$dir
Target[$target_name]: $volt1_oid&PseudoZero:$router_connect 
Options[$target_name]: nopercent,gauge,noinfo,noo 
Title[$target_name]: $router_name - DC Voltage in
PageTop[$target_name]: <h1> $router_name - DC Voltage in </h1>
 <table>
   <tr><td>System:</td><td>$html_sysdescr ($router_name)</td></tr>
   <tr><td>Maintainer:</td><td>$html_syscontact</td></tr>
   <tr><td>Resource:</td><td>DC Voltage  ($volt1_oid)</td></tr>
     </table>
MaxBytes[$target_name]: 1100
Ylegend[$target_name]: Volts DC * 10
ShortLegend[$target_name]: V DC * 10
LegendI[$target_name]: &nbsp;%:
Legend1[$target_name]: DC Volts in * 10
Legend3[$target_name]: Max DC Volts in * 10

ECHO
}

BTW, how hot is too hot for these things? Not ambient air, but the results of the sensor on the RB which those OIDs monitor. At what value do I want to set the alarm for Nagios? I’ve seen the spec sheets, but I believe they refer to operating environment rather than actual temperature of the silicon.

My temperature and voltage graphs flatlined again. We’ve been dealing with wind damage from a tornado so I haven’t had time to look at the graphs, or care for the last week or so.

lambert@dns1:~> snmpwalk -v1 -c sixr4ih59mdso gw1.mpt 1.3.6.1.4.1.14988.1.1.3
SNMPv2-SMI::enterprises.14988.1.1.3.9.0 = STRING: "n/a"
SNMPv2-SMI::enterprises.14988.1.1.3.10.0 = INTEGER: 450
lambert@dns1:~> snmpwalk -v1 -c sixr4ih59mdso gw1.mpt 1.3.6.1.4.1.14988.1.1.3
SNMPv2-SMI::enterprises.14988.1.1.3.8.0 = INTEGER: 115
SNMPv2-SMI::enterprises.14988.1.1.3.9.0 = STRING: "n/a"
SNMPv2-SMI::enterprises.14988.1.1.3.10.0 = INTEGER: 450
lambert@dns1:~> snmpwalk -v1 -c sixr4ih59mdso gw1.mpt 1.3.6.1.4.1.14988.1.1.3
SNMPv2-SMI::enterprises.14988.1.1.3.8.0 = INTEGER: 115
SNMPv2-SMI::enterprises.14988.1.1.3.9.0 = STRING: "n/a"
SNMPv2-SMI::enterprises.14988.1.1.3.10.0 = INTEGER: 450
lambert@dns1:~> snmpwalk -v1 -c sixr4ih59mdso gw1.mpt 1.3.6.1.4.1.14988.1.1.3
SNMPv2-SMI::enterprises.14988.1.1.3.8.0 = INTEGER: 115
SNMPv2-SMI::enterprises.14988.1.1.3.9.0 = STRING: "n/a"
SNMPv2-SMI::enterprises.14988.1.1.3.10.0 = INTEGER: 450
lambert@dns1:~> snmpwalk -v1 -c sixr4ih59mdso gw1.hs 1.3.6.1.4.1.14988.1.1.3
SNMPv2-SMI::enterprises.14988.1.1.3.9.0 = STRING: "n/a"
SNMPv2-SMI::enterprises.14988.1.1.3.10.0 = INTEGER: 400
lambert@dns1:~> snmpwalk -v1 -c sixr4ih59mdso gw1.hs 1.3.6.1.4.1.14988.1.1.3
SNMPv2-SMI::enterprises.14988.1.1.3.8.0 = INTEGER: 115
SNMPv2-SMI::enterprises.14988.1.1.3.9.0 = STRING: "n/a"
SNMPv2-SMI::enterprises.14988.1.1.3.10.0 = INTEGER: 400
lambert@dns1:~> snmpwalk -v1 -c sixr4ih59mdso gw1.ps 1.3.6.1.4.1.14988.1.1.3
SNMPv2-SMI::enterprises.14988.1.1.3.9.0 = STRING: "n/a"
SNMPv2-SMI::enterprises.14988.1.1.3.10.0 = INTEGER: 420
lambert@dns1:~> snmpwalk -v1 -c sixr4ih59mdso gw1.ps 1.3.6.1.4.1.14988.1.1.3
SNMPv2-SMI::enterprises.14988.1.1.3.8.0 = INTEGER: 111
SNMPv2-SMI::enterprises.14988.1.1.3.9.0 = STRING: "n/a"
SNMPv2-SMI::enterprises.14988.1.1.3.10.0 = INTEGER: 420
lambert@dns1:~>



[lambert@gw1.mpt] > /system routerboard print
       routerboard: yes
             model: "450G"
     serial-number: "279601792F55"
  current-firmware: "2.29"
  upgrade-firmware: "2.29"
[lambert@gw1.mpt] > /system package print
Flags: X - disabled 
 #   NAME                         VERSION                         SCHEDULED              
 0   routeros-mipsbe              4.17                                                   
 1   system                       4.17                                                   
 2 X ipv6                         4.17                                                   
 3 X wireless-nv2                 4.17                                                   
 4   routerboard                  4.17                                                   
 5   ppp                          4.17                                                   
 6   routing                      4.17                                                   
 7   dhcp                         4.17                                                   
 8   wireless                     4.17                                                   
 9   hotspot                      4.17                                                   
10   mpls                         4.17                                                   
11   security                     4.17                                                   
12   advanced-tools               4.17    

[lambert@gw1.hs] > /system routerboard print
       routerboard: yes
             model: "450G"
     serial-number: "2796017920B2"
  current-firmware: "2.29"
  upgrade-firmware: "2.29"
[lambert@gw1.hs] > /system package print
Flags: X - disabled 
 #   NAME                         VERSION                         SCHEDULED              
 0   system                       4.16                                                   
 1   hotspot                      4.16                                                   
 2   ppp                          4.16                                                   
 3   dhcp                         4.16                                                   
 4   routeros-mipsbe              4.16                                                   
 5   mpls                         4.16                                                   
 6 X wireless                     4.16                                                   
 7 X wireless-nv2                 4.16                                                   
 8   routerboard                  4.16                                                   
 9 X ipv6                         4.16                                                   
10   advanced-tools               4.16                                                   
11   security                     4.16                                                   
12   routing                      4.16

[lambert@gw1.ps] > /system routerboard print
       routerboard: yes
             model: "450G"
     serial-number: "2796017DDCC4"
  current-firmware: "2.29"
  upgrade-firmware: "2.29"
[lambert@gw1.ps] > /system package print
Flags: X - disabled 
 #   NAME                         VERSION                         SCHEDULED              
 0   system                       4.16                                                   
 1 X wireless-nv2                 4.16                                                   
 2   routerboard                  4.16                                                   
 3 X ipv6                         4.16                                                   
 4   mpls                         4.16                                                   
 5   routing                      4.16                                                   
 6   dhcp                         4.16                                                   
 7   routeros-mipsbe              4.16                                                   
 8   hotspot                      4.16                                                   
 9 X wireless                     4.16                                                   
10   ppp                          4.16                                                   
11   advanced-tools               4.16                                                   
12   security                     4.16

The flatline effect is less visible in the voltage graphs, so I won’t bother with posting an example of that. But if I dig out the magnification feature, I can see it happened at approximately the same time.