Why the "at" command is able to execute the jobs scheduled for past ?

Log in to Your Red Hat Account

Your Red Hat account gives you access to your profile, preferences, and services, depending on your status.

If you are a new customer, register now for access to product evaluations and purchasing capabilities.

Need access to an account?

If your company has an existing Red Hat account, your organization administrator can grant you access.

If you have any questions, please contact customer service.

Red Hat Account Number:

Red Hat Account

Customer Portal

For your security, if you’re on a public computer and have finished using your Red Hat services, please be sure to log out.

Log Out

Select Your Language

Issue

Rebooting was scheduled to be executed at specific date and time using "at" job. This was run on multiple servers. Some servers have been rebooted on the wrong time "meaning they have been rebooted immediately".
Why is at command executing jobs which are scheduled for the past ?

Environment

Red Hat Enterprise Linux (RHEL) 5
at-3.1.8-84.el5_11.1

Subscriber exclusive content

A Red Hat subscription provides unlimited access to our knowledgebase of over 48,000 articles and solutions.

Current Customers and Partners

New to Red Hat?

Learn more about Red Hat subscriptions

Welcome! Check out the Getting Started with Red Hat page for quick tours and guides for common tasks.

Here are the common uses of Markdown.

Code blocks

~~~
Code surrounded in tildes is easier to read
~~~

Links/URLs

[Red Hat Customer Portal](https://access.redhat.com)

Log in to Your Red Hat Account

Red Hat Account

Customer Portal

Select Your Language

Infrastructure and Management

Cloud Computing

Storage

JBoss Development and Management

JBoss Integration and Automation

Mobile

Services

Tools

Red Hat Product Security Center

Security Updates

Resources

Customer Portal Community

Customer Events

Stories