Based on your requirements, you are looking for a smart plug that can control a device like a firewall or a server running 24/7, is plugged into a UPS, and can be remotely accessed without the need for a VPN. Here are some recommendations within your budget of below 3K pesos:
1. TP-Link HS100 Smart Plug: The TP-Link HS100 is a budget-friendly smart plug that allows you to remotely control your devices from anywhere using the Kasa app. It supports scheduling, timers, and away mode. It should be compatible with your firewall or server setup.
2. Xiaomi Mi Smart Plug: Xiaomi offers an affordable smart plug that can be controlled remotely via the Mi Home app. It supports voice control through Google Assistant and Amazon Alexa, making it convenient to manage your devices.
3. Broadlink RM Mini 3: While not a traditional smart plug, the Broadlink RM Mini 3 is a smart IR controller that can turn on/off devices connected to it. You can control it remotely using the Broadlink app. It is a versatile option that can work with various devices.
Before making a purchase, ensure that the smart plug you choose is compatible with your specific firewall or server setup. Additionally, check if the smart plug can be accessed externally without VPN based on your requirements. These options should provide you with affordable solutions for remotely managing your devices.