This Network Update was distributed via the Exchange Network email alerts list on March 8, 2007.

Weekend Exchange Network and CDX Availability

This is a reminder that EPA's Central Data Exchange (CDX) will be undergoing maintenance this weekend. This maintenance is part of an ongoing effort to upgrade the servers that process data coming into EPA and provide core services on the Exchange Network such as authentication and quality assurance services.

On Saturday March 10th, Exchange Network partners may experience intermittent communication errors with EPA's production CDX Node between the hours of 6:00AM and 1:00PM EST. The CDX Node and NAAS in the pre-production or test environment will be unavailable from 6:00PM Friday March 9th through Sunday March 11th.

EPA will be scheduling other outages over the next 3 weekends with several more weekend outages tentatively scheduled in April and May. Exchange Network Partners may experience periods of unavailability during these times. If you intend to conduct data exchanges over the weekends, please consider following up with your exchange partners to confirm successful transactions during these times.

CDX Normal Production Operational hours are 24 hours a day 7 days a week, which includes a standard system maintenance time window between Friday 6pm - Monday 8am. Realistically it is understood that many Exchange Network partners continue to rely on CDX servers on weekends, so CDX provides system level Systems Administration and Operational support 7 days a week to minimize down-time for CDX as much as possible.

EPA apologizes for these inconveniences and looks forward to the improvements these upgrades will make to the Exchange Network.

More specific information will be provided as soon as it is available. EPA will also be posting notices and updates on CDX at: https://cdx.epa.gov/recent.asp