Not a great start to the day for Cisco employees, many of which are struggling in the face of an internal IT outage.

The technology and networking giant confirmed in a tweet it was “aware of some disruption” to its IT systems and is “working on restoring the network.

Worse, the company’s corporate blog also went kaput. For a period, Cisco’s blog was displaying the default WordPress install page. But at the time of publication, the blog had been restored.

Some customers were unable to login through Cisco’s single sign-on. Other customers couldn’t access licenses or downloads. But some of Cisco’s services, such as Webex, did not appear affected by the outage.

It’s not immediately clear exactly what caused the outage. Cisco spokespeople did not immediately respond to a request for comment.