Both Microsoft and Google had a bad day with their cloud services.

Microsoft’s cloud service Azure was hit by a two hour long outage for some of its key services on the 15th of September, while Google’s Apps for Work users in the UK and US were unable to use the service for over an hour on the 14th of September.

Microsoft’s problem stemmed from a domain name system malfunction that caused availability issues for services such as its SQL database, Virtual Machines and Azure backup. The company said the problem was caused by a spike in networking traffic.

The company said on its Azure status page: “A spike in networking traffic was experienced, which caused service-level drops for the DNS service. This resulted in connectivity issues for services reliant on DNS. Once network mitigation was implemented, most services fully recovered. Microsoft SQL Azure had secondary impact due to a misconfiguration.”

As with all cloud outages now Microsoft pledged that it would be publishing a full report into what happened, the report is expected within two days.

Google’s problem mainly impacted Gmail for Work users and it remained down for a few hours for some users.

The company has not revealed the reason for the outage but said on its status page: “We will conduct an internal investigation of this issue and make appropriate improvements to our systems to prevent or minimise future recurrences.”

Outages like these tend to be infrequent and typically safeguards are built into the cloud services to assure that some business continuity is maintained. However, problems like these can be damaging for the image of the cloud as a safe place for mission critical applications.

In reality the cloud is often much more stable than a traditional on-premise setup, but businesses are rightly wary about the potential consequences of a lengthy outage.

While there is growing reliance upon services provided by cloud vendors, there remains a necessity for having a continuity plan.