From the release notes for firmware 126.96.36.199 PNP (PNP) Agent—This agent resides on a switch and communicates with a PNP server, which allows centralized installation of configuration and image files to the switch. With the PNP agent and a PNP server, you can execute Zero Touch Installations of switches in various scenarios and locations. PNP operations reduce costs associated with deployment and installation of network devices, and increase the speed and reduce the complexity of deployments, all without compromising security. NOTE PNP is enabled by default on device. so beginning with this version, DHCP auto updating of the image and configuration is disabled by default. In previous version DHCP auto updating was enabled by default. How is this a _good_ idea? We have 1000+ SG300's out in the field, which use DHCP auto updating and, more importantly, DHCP auto configuration. As most, if not all, serious network devices support the feature of DHCP auto configuration we've implemented our own configuration solution which automatically provisions these SG300 devices and other Cisco Routers & Switches in our network as well as equipment from other brands. The SG350's supported this feature as well, making it our choice for the future. We use the SG300/SG350 as a simple CPE solution which made the feature of auto-configuration easy and replacing hardware a breeze. Now somebody thought it would be a good idea to disable this feature by default in favor of another feature which has no where near the wide support, breaks current existing setups and basically turns our current stock of SG350 with newer firmware into paperweights in an instant. There is no way to tell the SG350 to provision configuration over DHCP without configuring the SG350 manually first, which, well... ....defies the point doesn't it? A possible solution would be for a newer firmware version to switch between PNP and DHCP-Autoconfig on Boot based on the DHCP options passed to the device on boot. As it currently is, we have to downgrade our stock to turn them from paperweights to usable hardware which is labour-intensive, bad practice and never a good idea.
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