Nagios Support Forum

Hello Team,

We often receiving soft/hard alert for Bandwidth Status on some network devices only. We tried manually run and command and noticed below error. Please help us to resolve this issue.

Output:
[root@xxxxxxxxx libexec]# ./check_ifoperstatnag 37 -v3 -u nagios -A "xxxxxx" -a MD5 -l authNoPriv xx.xxx.xxx.xxx
buffer too small to read octet string (17 < 17)
snmpget: Timeout (Sub-id not found: (top) -> ifDescr)
buffer too small to read octet string (17 < 17)
snmpget: Timeout (Sub-id not found: (top) -> ifAdminStatus)
./check_ifoperstatnag: line 39: [: -eq: unary operator expected
buffer too small to read octet string (17 < 17)
snmpget: Timeout (Sub-id not found: (top) -> ifOperStatus)
UNKNOWN - No info is being retrieved.
[root@xxxxxxxxx libexec]# ./check_ifoperstatnag 37 -v3 -u nagios -A "xxxxxxx" -a MD5 -l authNoPriv xx.xxx.xxx.xxx
buffer too small to read octet string (17 < 17)
snmpget: Timeout (Sub-id not found: (top) -> ifDescr)
./check_ifoperstatnag: line 39: [: -eq: unary operator expected
UNKNOWN - No info is being retrieved.

Run the following(replace the Xs as appropriate) and provide the output:

Hello,

PFB output as requested

I just missed to say that network device is working fine for some time and multiple the services are getting flatting from OK state to unknown state from below output you can clearly see when i try running a command its giving output one time and another its giving timeout error.

When we checked in PROD all good and no issue noticed over there, we are facing issue in DR only.

Output:
[root@xxxxxxxxx ~]# snmpwalk -v3 -u nagios -A "xxxxxxx" -a MD5 -l authNoPriv xx.xxx.xxx.xx |grep 'ifDescr.37'
buffer too small to read octet string (17 < 17)
buffer too small to read octet string (0 < 17)
buffer too small to read octet string (0 < 17)
buffer too small to read octet string (0 < 17)
buffer too small to read octet string (0 < 17)
buffer too small to read octet string (0 < 17)
buffer too small to read octet string (0 < 17)
buffer too small to read octet string (0 < 17)
buffer too small to read octet string (0 < 17)
buffer too small to read octet string (0 < 17)
snmpwalk: Timeout
You have mail in /var/spool/mail/root
[root@xxxxxxxxx ~]# snmpget -D -v3 -u nagios -A "xxxxxx" -a MD5 -l authNoPriv xx.xxx.xxx.xx ifDescr.37
registered debug token v3, 2
buffer too small to read octet string (17 < 17)
buffer too small to read octet string (0 < 17)
buffer too small to read octet string (0 < 17)
buffer too small to read octet string (0 < 17)
buffer too small to read octet string (0 < 17)
buffer too small to read octet string (0 < 17)
buffer too small to read octet string (0 < 17)
buffer too small to read octet string (0 < 17)
buffer too small to read octet string (0 < 17)
buffer too small to read octet string (0 < 17)
snmpget: Timeout
[root@xxxxxxxxx ~]#

[root@xxxxxxxxx ~]# snmpget -D -v3 -u nagios -A "xxxxxx" -a MD5 -l authNoPriv xx.xxx.xxx.xx ifDescr.37
registered debug token v3, 2
IF-MIB::ifDescr.37 = STRING: GigabitEthernet1/0/30

[root@xxxxxxxxx ~]# snmpwalk -v3 -u nagios -A "xxxxxx" -a MD5 -l authNoPriv xx.xxx.xxx.xx |grep 'ifDescr.37'
IF-MIB::ifDescr.37 = STRING: GigabitEthernet1/0/30
IF-MIB::ifDescr.370 = STRING: GigabitEthernet6/0/28
IF-MIB::ifDescr.371 = STRING: GigabitEthernet6/0/29
IF-MIB::ifDescr.372 = STRING: GigabitEthernet6/0/30
IF-MIB::ifDescr.373 = STRING: GigabitEthernet6/0/31
IF-MIB::ifDescr.374 = STRING: GigabitEthernet6/0/32
IF-MIB::ifDescr.375 = STRING: GigabitEthernet6/0/33
IF-MIB::ifDescr.376 = STRING: GigabitEthernet6/0/34
IF-MIB::ifDescr.377 = STRING: GigabitEthernet6/0/35
IF-MIB::ifDescr.378 = STRING: GigabitEthernet6/0/36
IF-MIB::ifDescr.379 = STRING: GigabitEthernet6/0/37

How long does it take to return when it works? Try running:
You can try increasing the timeout with the -t option:

Hi,

As requested, PFB output

Output:
Not Working:
[root@xxxxxxxxx ~]# snmpget -D -v3 -u nagios -A "xxxxxx" -a MD5 -l authNoPriv xx.xxx.xxx.xx ifDescr.37 -t 20
registered debug token v3, 2
buffer too small to read octet string (17 < 17)
buffer too small to read octet string (0 < 17)
snmpget: Timeout
You have new mail in /var/spool/mail/root
[root@xxxxxxxxx ~]# time snmpget -D -v3 -u nagios -A "xxxxxx" -a MD5 -l authNoPriv xx.xxx.xxx.xx ifDescr.37
registered debug token v3, 2
buffer too small to read octet string (17 < 17)
buffer too small to read octet string (0 < 17)
snmpget: Timeout

real 0m6.042s
user 0m0.027s
sys 0m0.011s
[root@xxxxxxxxx ~]#

Working:
[root@xxxxxxxxx ~]# snmpget -D -v3 -u nagios -A "xxxxxx" -a MD5 -l authNoPriv xx.xxx.xxx.xx ifDescr.37 -t 20
registered debug token v3, 2
IF-MIB::ifDescr.37 = STRING: GigabitEthernet1/0/30
[root@xxxxxxxxx ~]# time snmpget -D -v3 -u nagios -A "xxxxx" -a MD5 -l authNoPriv xx.xxx.xxx.xx ifDescr.37
registered debug token v3, 2
IF-MIB::ifDescr.37 = STRING: GigabitEthernet1/0/30

real 0m0.031s
user 0m0.027s
sys 0m0.003s
[root@xxxxxxxxx ~]#

What OS/version is this XI server running on?

In doing some investigation it appears this was a problem in net-snmp

Are these Windows/Linux/Switch/Router?

I think it likely has something to do with the send/receive buffer size.

I know it can be set on the devices themselves so you might check the working vs non-working device configurations.

What is the output of this command (as root)?
If you don't have it you can create it in /etc/snmp/snmp.conf then add this to it:
Then see if the command still fails with the same message (make sure they both work), if they don't remove the line.

Hi Ssax,

Those are Switches.

We have checked on device configurations and found no issues.

Note:
It was working fine in PROD nagios xi and in DR also its working but often its fluctuating from OK to unknown state because of continuous timeout issue.

There is no /etc/snmp/snmp.conf file in the path, i have manually created and updated clientRecvBuf 249856 line.

log:
[root@xxxxxxxxx~]# find / -name snmp.conf
/etc/snmp/snmp.conf
/etc/cups/snmp.conf
find: ‘/proc/301’: No such file or directory
find: ‘/proc/304’: No such file or directory
find: ‘/proc/306’: No such file or directory
find: ‘/proc/307’: No such file or directory
find: ‘/proc/308’: No such file or directory
find: ‘/proc/309’: No such file or directory
find: ‘/proc/311’: No such file or directory

[root@xxxxxxxx~]# cat /etc/snmp/snmp.conf
clientRecvBuf 249856

Can you run the following as root and post the output here? Thanks

Hi Tgriep,

PFB output..

[root@xxxxxxxxxxx~]# snmpget -V
NET-SNMP version: 5.7.2
[root@xxxxxxxxxxx~]# cat /etc/*release*
NAME="Red Hat Enterprise Linux Server"
VERSION="7.8 (Maipo)"
ID="rhel"
ID_LIKE="fedora"
VARIANT="Server"
VARIANT_ID="server"
VERSION_ID="7.8"
PRETTY_NAME="Red Hat Enterprise Linux"
ANSI_COLOR="0;31"
CPE_NAME="cpe:/o:redhat:enterprise_linux:7.8:GA:server"
HOME_URL="https://www.redhat.com/"
BUG_REPORT_URL="https://bugzilla.redhat.com/"

REDHAT_BUGZILLA_PRODUCT="Red Hat Enterprise Linux 7"
REDHAT_BUGZILLA_PRODUCT_VERSION=7.8
REDHAT_SUPPORT_PRODUCT="Red Hat Enterprise Linux"
REDHAT_SUPPORT_PRODUCT_VERSION="7.8"
NAME="Red Hat Enterprise Linux Server"
VERSION="7.7 (Maipo)"
ID="rhel"
ID_LIKE="fedora"
VARIANT="Server"
VARIANT_ID="server"
VERSION_ID="7.7"
PRETTY_NAME="Red Hat Enterprise Linux"
ANSI_COLOR="0;31"
CPE_NAME="cpe:/o:redhat:enterprise_linux:7.7:GA:server"
HOME_URL="https://www.redhat.com/"
BUG_REPORT_URL="https://bugzilla.redhat.com/"

REDHAT_BUGZILLA_PRODUCT="Red Hat Enterprise Linux 7"
REDHAT_BUGZILLA_PRODUCT_VERSION=7.7
REDHAT_SUPPORT_PRODUCT="Red Hat Enterprise Linux"
REDHAT_SUPPORT_PRODUCT_VERSION="7.7"
Red Hat Enterprise Linux Server release 7.8 (Maipo)
Red Hat Enterprise Linux Server release 7.8 (Maipo)
cpe:/o:redhat:enterprise_linux:7.8:ga:server