net-snmp broken in RHEL (and Centos, of course) – diskio
I’ve had a belief for quite a while now that Linux, unlike other types of systems, was unable to produce any I/O SNMP information. I only recently found out that it was partially true – all production-level distros, such as RedHat (and Centos, for that matter) were unable to produce any output for any SNMP DISKIO queries.
I had found a bugzilla entry about it, so I raise the glove in a request to any of the maintainers of an RH-compatible repositories to recompile (and maintain, of course) an alternate net-snmp package which supports diskio.
Meanwhile, I have found this blog post, which offers an alternate (and quite clumsy, yet working) solution to the disk performance measurement issue in Linux. I haven’t tried it yet, but I will, rather soon.
I have used the script from the blog post mentioned above, and it works.
Speed could be an issue. Comparing two servers the speed differential was amazing.
Both servers are connected on the same switch as the server running the query is connected. Server1 has a P2 233MHz CPU, while Server2 has a dual 2.8GHz Xion CPU.
~$ time snmpwalk -c COMMUNITY -v2c Server1 188.8.131.52.4.1.2021.13.15 > /dev/null
~$ time snmpwalk -c COMMUNITY -v2c Server2 184.108.40.206.4.1.2021.13.15 > /dev/null
Looks like a huge difference. However, I believe it’s currently good enough for me.