[one-users] Host monitoring with snmp ?

[Neil Mooney]

Hi All,

I had some problems with host monitoring, namely that I could not
decrease the cycle time to monitor a host.
It is my understanding that we might need to monitor our hosts more
often to get better / fairer scheduling.

I changed HOST_MONITORING_INTERVAL setting to 10 seconds, but I could
not realise a cycle time of less than 30 seconds...

oneadmin at node15-one:~$ grep INTERVAL /etc/one/oned.conf
#  HOST_MONITORING_INTERVAL: Time in seconds between host monitorization
#  VM_POLLING_INTERVAL: Time in seconds between virtual machine
monitorization
HOST_MONITORING_INTERVAL = 10
VM_POLLING_INTERVAL      = 60

I wrote a script that tries to emulate the ruby monitoring script, but
pulls the information directly from system snmp counters to
This should mean a more real time status of each host and avoids parsing
out, scp and ssh of the ruby script.

Is host monitoring via snmp a good idea ? Perhaps its  faster / more
scalable ?

Example output using the ruby script from ONE:

oneadmin at node15-one:~$ time
/tmp/one-im/one_im-7a0979c4d3d29cded6cdb99498449870
HYPERVISOR=kvm
TOTALCPU=800
CPUSPEED=2261
TOTALMEMORY=24735424
USEDMEMORY=10151572
FREEMEMORY=24159416
FREECPU=770.4
USEDCPU=29.6
NETRX=18837297726
NETTX=328653416717

Example output from my snmp script:

real    0m3.531s
user    0m0.000s
sys     0m0.028s
oneadmin at node15-one:~$ time scripts/onemonitor.sh node16-one
HYPERVISOR=kvm
TOTALCPU=800
CPUSPEED=2270
TOTALMEMORY=24735424
USEDMEMORY=18889772
FREEMEMORY=5845652
FREECPU=0.00
USEDCPU=800.00
NETRX=513353459
NETTX=3422880146

real    0m0.039s
user    0m0.012s
sys     0m0.048s
oneadmin at node15-one:~$ time scripts/onemonitor.sh localhost
HYPERVISOR=kvm
TOTALCPU=800
CPUSPEED=2270
TOTALMEMORY=24735424
USEDMEMORY=9011744
FREEMEMORY=15723680
FREECPU=792.00
USEDCPU=8.00
NETRX=513356316
NETTX=3422883584

real    0m0.039s
user    0m0.020s
sys     0m0.040s
oneadmin at node15-one:~$

Cheers

Neil