In January 2015 the International Earth Rotation and Reference Systems Service (IERS) announced an induction of a leap second to be added on June 30, 2015. A leap second is a one-second adjustment that is sometimes added to help correct Coordinated Universal Time (UTC), which can depart from atomic time due to irregularities in the earth’s rotation.
You might be asking yourself: why is this important? The last time a leap second was inducted was 2012, and it was reported that many public websites and corporations experienced outages due to a bug in Unix kernel based systems.
With the large umbrella covered by the Unix kernel in today’s infrastructure, this could affect you. Fortunately, vendors, such as Cisco, have already started their own internal analysis and are sharing what products are directly affected. Since AHEAD is a trusted Cisco partner, it is our priority to ensure our clients are informed about the impact of the new leap second.
Cisco has reviewed records from previous induction years, 2008 and 2012, and found a limited number of defects spanning several platforms, but there were limited reported outages. Cisco released the following statement about the prior events:
As part of Cisco’s preparation for the 2015 leap second, we completed a comprehensive review of past customer support cases. This included a detailed search of service requests, defects, and bug reports, focusing on the period one week either side of the 2008 and 2012 leap second introductions.
We assessed the related records for both periods, spanning all Cisco platforms and all Cisco customers, and found a limited number of defects and service requests. Although one of these customers required a system reboot to recover, most experienced synchronization alarms that were easily and quickly resolved with support from the Cisco Technical Assistance Center (TAC). As a result, we do not believe that the 2008 or 2012 leap seconds represented a material event for our products or customers. (Source)
Even with the limited amount of reports in previous leap second inductions, it’s important to highlight that there are several platforms with documented bugs that will cause serious issues to various environments. I have highlighted these platforms in the table below:
A full list of affected products and bug IDs published by Cisco can be found below. It is highly recommended to use the list to help assess your infrastructure with the currently affect products and versions. Follow this link to view the full list of products that are NOT affected and have no expected impact.
If you have any questions regarding the leap second or remediation, please contact us. We’d be happy to have a conversaion with you. You can also learn more about the latest networking technologies in the AHEAD Lab and Briefing Center.