Solved

Malformed packets from 127.0.0.1 every ~62.5 seconds

Posted on 2016-09-19
4
41 Views
Last Modified: 2016-10-09
On a 2008r2 Domain Controller, with Exchange Exchange 2010 installed (I am very aware that this is not optimal, but when you inherit a client network...)

Event ID 5502 repeated every ~62.5 seconds with the text

The DNS server received a bad TCP-based DNS message from 127.0.0.1.  The packet was rejected or ignored. The event data contains the DNS packet.

Open in new window


As Wireshark is unable to capture from loopback, I used RawCap  to capture traffic on the loopback interface for several minutes, and then opened up the capture in WireShark, which shows a repeated malformed packet as per the attached.

While I have stopped the event from showing by changing DNS event logging from "All events" to "Errors and warnings", I am interested in why might be causing this, especially with the frequency of recurrence...
0
Comment
Question by:ArneLovius
  • 3
4 Comments
 
LVL 62

Expert Comment

by:gheist
ID: 41806861
Is it some montiring script checking DNS is up with TCP? like nagios/zabbix whatever?
0
 
LVL 37

Author Comment

by:ArneLovius
ID: 41806989
I haven't found anything obviously scheduled, and as the source is 127.0.0.1 it has to be local to the server.

The cycle time of ~62.5 seconds makes me think that its an internal process rather than a scheduled one, but I'm quite happy to admit that I;m stumped by it :-)
0
 
LVL 62

Accepted Solution

by:
gheist earned 500 total points (awarded by participants)
ID: 41807346
nslookup timeout is 2s. so something sleeps 1min, then does nslookup then sleeps again.
0
 
LVL 62

Expert Comment

by:gheist
ID: 41835700
Hard to guess better.
0

Featured Post

Best Practices: Disaster Recovery Testing

Besides backup, any IT division should have a disaster recovery plan. You will find a few tips below relating to the development of such a plan and to what issues one should pay special attention in the course of backup planning.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

There have been a lot of times when we have seen the need to enter a large number of DNS entries in a forward lookup zone. The standard procedure would be to launch the DNS Manager console, create the Zone and start adding new hosts using the New…
Resolve DNS query failed errors for Exchange
To efficiently enable the rotation of USB drives for backups, storage pools need to be created. This way no matter which USB drive is installed, the backups will successfully write without any administrative intervention. Multiple USB devices need t…
This tutorial will walk an individual through configuring a drive on a Windows Server 2008 to perform shadow copies in order to quickly recover deleted files and folders. Click on Start and then select Computer to view the available drives on the se…

776 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question