17 Oct 2011
- Simple DNS Plus v. 5.2 build 120 released
Simple DNS Plus v. 5.2 build 120 is now available at http://www.simpledns.com/download.aspx.
The update fixes a bug where a zone's DNSSEC signatures would not be re-loaded after some types of API updates / on secondary servers after receiving zone transfer.
06 Aug 2011
- Simple DNS Plus v. 5.2 build 119 released
Simple DNS Plus v. 5.2 build 119 is now available at http://www.simpledns.com/download.aspx
This update consists of the following 3 enhancements:
1) New "Also Notify" feature.
Send NOTIFY requests to IP addresses not listed in NS-records when primary zone is updated.
This can be specified in the Zone Properties dialog under a new "Notify" tab:
And the default for new zones can be specified in the Default Zone Values dialog under a new "Notify" tab:
2) The DHCP Server plug-in now supports "infinite" lease period.
3) For Shadow forwarding, you can now specify the value of response AA-flag.
Either set, copy (from forward server response), or clear:
This is NOT a critical update, and you only need to update if you want / need the updates included.
18 Feb 2011
- New "TFTP Server" plug-in
This new plug-in provides TFTP (Trivial File Transfer Protocol) server functionality.
TFTP is typically used in combination with DHCP to enable PXE / diskless booting of PCs, provisioning IP phones, etc.
An example of how to use this is provided in KB1304 - How to serve a network based Debian Linux installation with Simple DNS Plus.
Download: tftp-plugin.zip (14 KB)
Un-zip the file to the "plug-ins" sub-directory under the directory where Simple DNS Plus is installed. After this it will be available in the Simple DNS Plus Options dialog / Plug-Ins section.
This plug-in is free of charge and can be used with Simple DNS Plus v. 5.2 build 111 and later - any license size.
For more information about this plug-in see KB1302
18 Feb 2011
- Simple DNS Plus v. 5.2 build 118 released / Enhanced DHCP Server plug-in
Simple DNS Plus v. 5.2 build 118 is now available at http://www.simpledns.com/download.aspx.
This update includes an enhanced version of the DHCP Server plug-in - with the following new features:
- Added DHCP options "TFTP Server" (a.k.a. "Next-Server") and "Boot file name".
These options are typically used in combination with a TFTP server to enable PXE / disk less booting of PCs, provisioning IP phones, etc.
(we also just release a new TFTP server plug-in)
An example of how to use this is provided in KB1304 - How to serve a network based Debian Linux installation with Simple DNS Plus. - Ability to override most options (lease time, default gateway, static routes, DNS servers, TFTP server, boot file) per reservation / reservation group.
- Ability to provide at host name to clients with MAC based reservation.
- Ability to limit DHCP clients to reservations (ignore DHCP requests from clients with no reservation).
See the updated DHCP Server plug-in user interface and documentation at http://www.simpledns.com/kb.aspx?kbid=1216
The update also include a bug fix - for details on this and previous releases,please see release notes.
This is NOT a critical update, and you only need to update if you need to fixes / updates included.
19 Dec 2010
- Updated DHCP Server plug-in released
We have added an option to supply static routes (in addition to the default gateway) to DHCP clients. In technical terms, the plug-in now supports DHCP parameter 121 / 249.
It it now also possible to not assign Simple DNS Plus as the preferred DNS server (by disabling the first option highlighted below), and to re-order DNS server IP addresses according to preference (using the Up/Down buttons highlighted below):
This updated plug-in works with Simple DNS Plus v. 5.2 (any build) and can be downloaded from http://www.simpledns.com/outbox/plugins/v52/dhcp-5-2-118.zip
To install, shutdown Simple DNS Plus, unzip above file to the Plugins folder under the directory where Simple DNS Plus is installed (replacing the older version of the plug-in .dll), and start Simple DNS Plus again.
This updated plug-in will also be included with future builds of Simple DNS Plus v. 5.2 (build 118+).
31 Aug 2010
- Atom Publishing Protocol (AtomPub) server library for ASP.NET
Just released - for details click here
10 Aug 2010
- New reports of DNS amplification / DDoS attacks
Over the past few days, a number of Simple DNS Plus users have reported that they are receiving a lot of incoming DNS requests for <root> and/or various unknown domain names - typically originating from a limited number of IP addresses. We have also noticed reports of this with other DNS servers on various forums etc.
If you see something similar, this may be an indication that someone is abusing your DNS server as part of a so-called DNS amplification attack against a third party - the owner of the IP address that the DNS requests appear to originate from.
By sending a DNS request from a spoofed IP address, the attacker attempts to trick your DNS server into sending a DNS response packet to the victim and thereby become part of a DDoS attack. Typically the request is designed to trigger a response packet which is larger than the original request packet - thus the amplification.
We do NOT recommend blocking the sender's IP address on your firewall, with IPSec, or anything else at the IP address level - that is exactly what the attacker wants you to do! By blocking the apparent sender IP addresses, you are really blocking the victim rather than the attacker - because the sender IP address is spoofed as the victim's.
The aim of the attack is twofold: (1) overload the victim's Internet connection with large DNS responses, and (2) make everybody firewall the victim, so he can't use his connection even after the attack.
The best way to counter this type of attack is to make your DNS server unattractive as a "way-point". You do this by configuring Simple DNS Plus to either ignore or refuse lame requests.
First, in the Options dialog / DNS / Resolver / Recursion section, either turn off recursion completely if you don't need it, or limit it to your own IP address range(s):
Then, in the Lame Requests section, select either "Respond with a Refused error message" or "Do not respond":
Generally we recommend using the "Refused" option as this makes it easier to troubleshoot other DNS issues. However if this attack is continuously hitting your server, you will do the victim a favor using the "Do not respond" option. When no longer under attack, you can switch to the "Refused" option which still ensures that your server is not attractive as a way-point for this type of attack - since it won't amplify traffic.
If the requests are mostly for <root>, another way to deal with this traffic, and keep it out of the log at the same time, is the "Ignore all DNS requests for <root>" feature found in the Miscellaneous section:
31 Jul 2010
- Simple Failover v. 2.0
We are working on the next major version of
Simple Failover, and we would like to hear your feedback on the planned new features. There is also still time for adding more new features if you have a good idea.
See the list of new features at
http://www.simplefailover.com/kb.aspx?kbid=1298
Simple Failover is a software product which continuously monitors your servers (any networked device/service) to see which are up and which are down, and then dynamically updates your DNS records accordingly so that your domain name always points to a functional server. Additionally it can notify you of any encountered problems.
This upcoming v. 2.0 will of course be covered by our one year free upgrade protection. If you purchase a license for the current Simple Failover version today, you will receive a free upgrade to v. 2.0 when this is released.
Please e-mail us your thoughts and ideas, or post below, or in the all new
community forums
We look forward to hearing from you.
09 Jul 2010
- Simple DNS Plus v. 5.2 build 117 released / Problem resolving WebMD.com
Simple DNS Plus v. 5.2 build 117 is now available at http://www.simpledns.com/download.aspx
For more details on the updates and changes in this build, please see release notes.
Over the last few days, several users have reported not being able to resolve www.webmd.com.
The problem is an erroneous response (details below) from the DNS servers hosting the domain name.
We have contacted WebMD.com and their DNS provider (UltraDNS) about this and anticipate that they will fix the problem shortly.
However since WebMD.com is a very popular web-site (and UltraDNS is one of the larger DNS providers), we felt it was best to provide a quick workaround with above update to Simple DNS Plus.
When we do a lookup for www.webmd.com against one of the authoritative DNS servers (for example "pdns1.ultradns.net"), we get a response with a CNAME-record (alias) pointing to www.phx1.webmd.com and a SOA-record in the authority section:
The standard (RFC) interpretation of this SOA-record is that no records exist for the current name (www.phx1.webmd.com) and the requested record type (A) - a so called "NO DATA" response.
Therefore previous builds of Simple DNS Plus naturally stopped the resolving process here - no need to do anything more since we know the final answer (no data).
However if we do another DNS lookup for www.phx1.webmd.com against the same DNS server, we get a surprising response - now all of a sudden there IS an A-record for this name:
This is an error in the configuration or operation of the DNS servers hosting www.webmd.com, and we obviously recommend that they get this fixed as quickly as possible.
In this new build of Simple DNS Plus, we have made an exception for this very specific situation:
For responses received containing a CNAME-record in the Answer section, a "NODATA" SOA-record in Authority section is now ignored, and the CNAME alias is attempted resolved in a new outbound request.
This immediately makes it possible for Simple DNS Plus to resolve www.webmd.com and any other domain with the same problem.
The trade off is that this will also cause a few more outbound requests in certain situations. These extra requests would normally not be necessary, but it does make Simple DNS Plus more resilient against this type of problem.
17 Dec 2009
- Expiration of support for Simple DNS Plus v. 4.00
Note that from January 17th 2010 we will no longer provide support for Simple DNS Plus v. 4.00 (or earlier versions).
As per our
Support Life-Cycle Policy, a Simple DNS Plus version is supported for 3 years after it is first released, and for 2 years after we stop selling it (whichever comes last).
V. 4.00 was originally released on April 10th 2005, and we stopped selling it on January 17th 2008 when v. 5.0 was released.
We encourage users of v. 4.00 and earlier version to
upgrade to the current v. 5.2.
For details on all the new features and other improvements see:
v. 5.0:
http://www.simpledns.com/kb.aspx?kbid=1215
v. 5.1:
http://www.simpledns.com/kb.aspx?kbid=1246
v .5.2:
http://www.simpledns.com/kb.aspx?kbid=1265