Cisco AsyncOS release terminology uses the following nomenclature:
A Cisco software release that provides new features and new platform support, in addition to bug fixes. This is intended for early adoption by customers. [This was formerly called First Customer Ship (FCS).]
AsyncOS 9.0.0 build 087 upgrade For Management, 2015-1-30, is a release available for Early Deployment
A Cisco software release that provides new features and new platform support in addition to bug fixes which is ready for deployment anywhere in customer networks where the features and functionality of the release are required. [This was formerly called General Availability (GA).]
AsyncOS 13.0.0 build 392 upgrade For Email, 2020-02-03. This release is for General Deployment.
A Cisco software release that is only applicable to a small subset of users. This could be for supportability and or compatibility reasons, based on the version of the software released, or platform the software supports.
AsyncOS 13.5.0 build 263 upgrade For Email, 2020-03-15, release available for Limited Deployment.
If there is an LD release available from the Release Notes listing for your appliance and you are not seeing the LD release on your appliance, please open a Cisco Support case, as it may require provisioning.
A Cisco software release that provides bug fix support and ongoing software maintenance.
AsyncOS 8.5.1 build 019 upgrade For Web, 2015-1-26, is a release available for Maintenance Deployment
A Maintenance Deployment (MD) outweighs a General Deployment (GD). Cisco will utilize Maintenance Deployments to deliver the latest version of a software release that includes a customer/field suited fix and additional updates.
A Cisco software targeted release for a customer to address specific critical product bug(s).
AsyncOS 8.0.1 build 113 upgrade for Email, 2015-02-12, this release is available as a Hot Patch HP5
HP requires special provisioning for a customer appliance(s). Customers will need to open a support request with Cisco Support. Cisco Support will work directly with the customer in order to approve and complete the provisioning accordingly.
To open a support request, please visit Cisco's Support Case Manager.
Updated 5 months ago