OnPlus for site survey (pre-MSP-sale): Getting lots of "DNS Has No records": More explanation/how to broach w/ prospect?

[davebainum]

Hi all,

We currently have an OnPlus connected at a prospective client site for whom we're in the process of writing an IT Services proposal.

We're getting a TON of DNS alerts saying "DNS 192.168.0.2 has no records".  Then, occasionally an alert that says "DNS ok".  But, a lot of them that are saying "DNS has no records"...

We already know that the prospect's current network and server environment is - shall we say delicately - "less than optimal"...  Really old PC's and servers, a crummy switch; a tired, sad, unremarkable ISP; insufficient backup power; crummy phones; various PC issues; the list goes on and on.  However, I wanted to dig a little deeper into the DNS messages, just because we haven't really seen those with such intensity before.

Does this alert essentially mean that the DNS server is not properly resolving DNS names or not doing so in a timely manner?  Does this alert generate if just the primary DNS is problematic, or would it fire for secondary DNS server lookup issues as well?  In other words, what is the likely user impact being experienced when an alert is being received?  We know that the prospect is still functioning, but we would not be at all surprised if their DNS setup is not the way it should be - either that the on-site DNS is not configured right, it's overloaded, maybe they failed to set up a backup or secondary DNS, etc..

This particular prospect's OnPlus device is configured for DHCP, since it is a possible client (prospect), not a current client.  However we very much hope they will become a client.  ;-)

Thanks in advance!...

-- Dave Bainum, PMP* (dbainum@ritetech.net)

RiteTech LLC / www.ritetech.net / Tel. +1 (703) 561-0607

[*PMP=PMI Certified Project Management Professional]

[afullfor]

Dave,

The OnPlus Agent's DNS Monitor exercises the DNS servers from its configuration (either static or found via DHCP).

The default test tries to resolve www.cisco.com.  This particular error means that the DNS server responded but for whatever reason, it could not resolve www.cisco.com.  There is a separate alarm if there was no response within the specified time (defaults are 15 seconds warning, 20 seconds critical).

www.cisco.com should be rapidly resolvable just about anywhere on the internet, but there may be some cases where this is not a useful choice, so you can change the hostname.

As the IP address of the DNS server appears to be on the local network, the problem may be with it, or if this is a NAT router set to forward DNS queries, the problem could be with the upstream provider.

Andy

[JOHN NIKOLATOS]

Just to let you know - I have the same alerts come across my box.. on a new server.  It is a SBS2008 server and I have been noticing a lot of those messages as well. 

[Michael Holloway]

Hi Dave and John,

We're looking into this issue currently, this looks like a bug in the DNS monitor with processing certain nameserver responses.

[Michael Holloway]

Dave, John,

We've addressed this bug in our current development version by moving away from the deprecated nslookup tool (now using dig). I'll work with our dev-test folks to make sure that we get this fix into the next release.