It’s time to expand DNS Check’s footprint, this time to Europe.

We just added a new name server hosted by Amazon Web Services in Ireland. The server’s hostname is ireland1.dnscheck.co, and its IPv4 address is 52.48.61.155. No IPv6 address is assigned yet, although we plan to add one in.

This new name server joins our existing IPv4 and IPv6 capable name servers in New York and San Francisco.

DNS Check customers can query our new ireland1.dnscheck.co name server for more direct testing of European hosted DNS services.

Customers who use DNS Check’s default name servers will start to see a portion of their queries come from ireland1.dnscheck.co automatically.

Professional customers who would like to query ireland1.dnscheck.co directly can do so by entering ireland1.dnscheck.co in a DNS record group’s Name server field.

We’ve made a number of updates to DNS Check’s user interface to improve usability over the past couple weeks. Some of the more noteworthy updates are:

1. Added a search bar to the top of each DNS record type section. This allows you to search your monitored DNS records by name or value.

2. DNS records are now sortable by their pass/fail status, name, and value.

3. Added a mass delete feature. Previously, DNS records could be deleted individually, or an entire DNS record group could be deleted. Now you can also select multiple DNS records to delete at a time.

4. Cut the number of steps required to create a DNS record group, and import monitored records into it.

5. Replaced the Flash based copy buttons with JavaScript based copy buttons.

6. Improved usability on mobile devises.

7. Speed up DNS zone file imports.

We also made a number of smaller updates which we hope you’ll like.

Check out our example DNS Check to see some of these updates in use.

We’d love to have your feedback. Please contact us, or leave a comment below if you have any suggestions for improvement.

Today we’re releasing two closely related features - the DNS Check API, and the DNS Check Integrations Directory. These features enable DNS Check to better integrate with third party services.

DNS Check API

The DNS Check API is REST API which enables checking on the status of monitored DNS records, and record groups.

An example use case of the API is to augment monitoring systems that have limited DNS record checking capabilities. Many monitoring services support checking A and AAAA records, but lack support for checking other DNS record types, such as MX and SPF records.

We’ve written two integration guides which provide examples of how the DNS Check API can be used to fill this monitoring gap:

• Nagios / DNS Check Integration Guide
• Pingdom / DNS Check Integration Guide

The DNS Check API is available to both free and paid accounts.

DNS Check Integrations Directory

We’re also releasing the DNS Check Integrations Directory. This is a directory of third party services that integrate with DNS Check. Integrations currently fall into two categories:

• Integrations where DNS Check pushes information as DNS record change state between passing and failing. Examples include Slack and PagerDuty.

• Integrations where a third party periodically polls DNS Check for information using DNS Check’s API. Examples include Nagios and Pingdom.

We plan to expand the number of available integration options.

Please contact us if you’re interested in integrating with DNS Check, and having your app listed in the integrations directory.

We’re proud to announce that DNS Check has integrated with Flowdock to provide reliable DNS record and name server monitoring with real-time notifications. This integration combines the strengths of DNS Checks’s DNS monitoring service with Flowdock’s chat service. It also allows you to receive notifications from DNS Check, coworkers, and and other monitoring systems through a common Flowdock interface.

Flowdock is a team collaboration app for desktop, mobile & web. Flowdock enables you chat, notify and share files in real-time.

DNS Check enables you to easily monitor, share and troubleshoot DNS records. You can import DNS your zone file and have DNS Check monitor the records in it, or specify individual records that you would like monitored.

You can designate that a DNS record is “exclusive,” meaning it should be the only DNS record of its name / record type combination. For example, the MX record for your company’s domain name should be the only MX record for that domain.

You have the option of making each set of DNS records publicly visible, or private, which can save precious seconds if a DNS record or name server is broken, but the person who maintains it doesn’t normally have access to your monitoring system. Here’s an example set of public DNS record checks.

We’ve developed a REST API which enables checking on the status of DNS records, and record groups that are monitored through DNS Check.

An example use case of the API is to augment monitoring systems that have limited DNS record checking capabilities. For example, many services support checking A and AAAA records, but lack support for checking MX and SPF records.

We plan to make the DNS Check API available to both free and paid accounts.

The API is currently in beta. Please contact us if you’re interested in being a beta tester.

We plan to end the beta period, and make the API available to all of our customers on November 16th.

We just added a new feature which allows you to enable or disable notifications on a per DNS record group basis:

Prior to this update, notifications were permanently enabled for all DNS record groups. Now they’re enabled by default, with the option to turn them off.

Your remaining notification options still get configured by navigating to the “Users” menu in the top-right corner of DNS Check’s website, then selecting “Notification Options”. Once there, you can choose to enable or disable Email, OpsGenie, PagerDuty and VictorOps notifications.

MX, or Mail Exchange records are DNS records that specify which mail servers are responsible for receiving email for a domain. When someone sends you an email, their mail server looks up the MX records for your domain (the part of the email address after the @ sign), and attempts to deliver the message to a mail server that’s specified by those MX records.

If MX records are improperly configured, then legitimate email may not get delivered to you, and spam may find a way to bypass your spam filter’s checks.

This post provides some background on how MX records work, followed by suggestions on how to check them.

MX Record Structure

Each domain name can have one or more MX records, and each MX record has two fields - the “Preference” and “Exchange”.

Preference

An MX record’s “Preference” value is a number between 0 and 65,535 which indicates how preferable that record is relative to other MX records for the same domain. If a domain only has one MX record, then the Preference doesn’t matter. When more than one MX record exists for a domain, the MX record with the lowest Preference is checked to decide which “Exchange”, or mail sever to attempt to deliver mail to first.

Having the lower Preference win can seem counter intuitive, so the Preference is also sometimes called the MX record’s “distance”.

If two or more MX records tie for lowest Preference value, then the sending mail server randomly picks one for the first delivery attempt.

If the first delivery attempt fails, then the sender attempts to deliver the message to the MX record with the next lowest Preference. This process repeats until the sender either succeeds in contacting a mail server, or runs out of MX records to check.

We’re proud to announce that DNS Check has integrated with OpsGenie to provide fast, reliable DNS record and name server monitoring with notifications. This allows you to combine the strengths of DNS Checks’s DNS monitoring service with OpsGenie’s notification service. It also allows you to receive notifications from both DNS Check, and other monitoring systems through a common OpsGenie account.

OpsGenie enables you to transform alerts into notifications that are sent to users via iPhone, Android, Blackberry push notifications, email, SMS and phone calls.

DNS Check enables you to easily monitor, share and troubleshoot DNS records. You can import DNS your zone file and have DNS Check monitor the records in it, or specify individual records that you would like monitored.

You can designate that a DNS record is “exclusive,” meaning it should be the only DNS record of its name / record type combination. For example, the MX record for your company’s domain name should be the only MX record for that domain.

You have the option of making each set of DNS records publicly visible, or private, which can save precious seconds if a DNS record or name server is broken, but the person who maintains it doesn’t normally have access to your monitoring system. Here’s an example set of public DNS record checks.

Alerts are automatically created in OpsGenie when a DNS record check fails, and resolved when the DNS record check starts passing again.

We just added SOA record monitoring to DNS Check.

SOA, or Start of Authority resource records are DNS records that define a number of global parameters for a DNS zone, or domain.

An SOA record’s Serial Number normally gets updated each time the zone file is updated. This makes monitoring the SOA record an idea that’s worth considering for infrequently modified zone files, since monitoring a single record normally has the effect of monitoring all records in the zone file for changes. We still recommend monitoring the remaining DNS records, since it’s not guaranteed that the Serial Number will be updated. Think of SOA record monitoring of one layer of a multi-layered DNS record monitoring system.

If a zone file is updated frequently, then you may decide to exclude its SOA record from monitoring. To do this, just delete the SOA record from the DNS Check DNS record group after importing the zone file.

Each zone file should contain a single SOA record.

DNS is the Achilles heel of many monitoring systems. They often allow you to monitor A and AAAA records, which resolve domain names to IP addresses, but lack support for other DNS record types. They also often lack support for detecting incorrectly duplicated DNS records.

If this Achilles heel is present in your monitoring system, it could cause a failure to detect downtime in your production systems.

For example, if a conflicting MX record is created, will you get notified by your DNS monitoring system immediately, or by your users later when they notice that they’re no longer receiving emails?

Security is another concern. If NS records get hijacked for a phishing attack, will you get notified by your DNS monitoring system immediately, or will it go unnoticed?