Coxxs

How to activate Synology Active Backup for Business without Internet

Synology DSM’s Active Backup for Business suite is a great backup solution, but after the initial installation or reinstallation, it requires activation with a Synology account to use.

Active Backup for Business is great, but it requires logging into an account and online activation for first-time use

However, I don’t like offline software that requires online activation to function — if the server fails or goes offline one day, or if there’s a local network issue, and I happen to have reinstalled the software, it becomes unusable.

There are several methods circulating online for local activation of such suites, but they are quite complex. So, I spent some time write a simple and universal activation method for future use.

Fixing Ultra 7 265K’s Frequent Stuttering

Perhaps because Intel realized their new products weren’t selling, the Core Ultra 200S series CPUs have seen significant price cuts. I took the opportunity to build a new PC with an Intel Core Ultra 7 265K, temporarily using the integrated graphics. While the Core Ultra 200S isn’t great for gaming performance (especially online games), for users like me with long uptime needs and a 4K monitor who don’t play online games, the 265K is quite suitable — it’s highly power-efficient at idle and very quiet with air cooling.

The motherboard is an MSI PRO Z890-A, which only provides one HDMI port for video output. Although this motherboard’s HDMI supports 4K 120Hz, due to bandwidth limitations, the color format downgrades from RGB to YUV420. This results in visible color fringing around small text. However, the motherboard has 2 × Thunderbolt 4 ports, and using a Thunderbolt/USB 4 cable to connect to the monitor allows for DP protocol output at 4K 144Hz with RGB (using DSC compression, but the difference is imperceptible to the naked eye).

Enables Accessibility Features for Sideloaded Apps on Android 15

I recently got a new phone and installed Smart AutoClicker to automatically click the skip button while idling in single-player games. However, on the accessibility settings page, I couldn’t grant the clicker permission.

Even after clicking to enable, the switch immediately turns off automatically

Stock Android shows a “Restricted Settings” prompt

I tried using an adb command (adb shell settings put secure enabled_accessibility_services ...), but it still didn’t work. After checking logcat, I found this error:

Skipping enabling service disallowed by device admin policy: ComponentInfo{com.buzbuz.smartautoclicker/com.buzbuz.smartautoclicker.SmartAutoClickerService}...

After looking into the Android codebase, I realized it’s due to a new security mechanism introduced in Android. Taking this opportunity, I’ve compiled a few solutions for those who need them.

Enable TCP BBR v2 on Linux & Windows 11

BBR is a TCP congestion control algorithm developed by Google. It improves upon the shortcomings of traditional congestion control algorithms (like CUBIC), which reduce speed upon packet loss, significantly enhancing bandwidth utilization in high packet loss environments.

It’s important to note that congestion control algorithms manage the packet sending rate. For example, if a Google server enables BBR, its upload speed will maximize the available bandwidth; from the user’s perspective, this results in faster download speeds.

As is well known…

Many people enable BBR on their Linux servers with just a few commands:

echo "net.core.default_qdisc=fq" >> /etc/sysctl.conf
echo "net.ipv4.tcp_congestion_control=bbr" >> /etc/sysctl.conf
sysctl -p

As a result, when downloading files from the server, it utilizes the full bandwidth. However, when uploading files, the speed remains slow because the system used for uploading is still running a traditional congestion control algorithm.

ESXi 7.0 + R8168 / R8169 Installation Notes

Installing ESXi on an unsupported device is a matter of luck. Unfortunately, I found that my computer’s built-in NIC is a Realtek R8168 — a network card no longer supported by ESXi.

In the ESXi 6.x era, we could add the net55-r8168 driver to make ESXi support this NIC, but after ESXi 7.x disabled all Linux-dependent drivers, this method no longer works.

Mysteries of Telegram DC

Telegram claims to have 5 data centers (DCs), referred to as DC1~5 in Telegram’s code and documentation. Among them, DC1 and DC3 are located in Miami, USA; DC2 and DC4 are in Amsterdam, Netherlands; and DC5 is in Singapore.

Each account is associated with a DC upon registration and does not change with the user’s phone number or geographic location. Users cannot freely choose a DC—if connected to the wrong DC, the server returns an error message, requiring the client to connect to the correct DC associated with the account.

Optimizing my Surface Pro 8

Windows 11 has significantly improved the touchscreen experience and added support for native Android emulation, making me want to try a touch-enabled Windows 2-in-1 device again. Coinciding with the release of the Surface Pro 8, this model ditches the 6-year-old thick-bezel design, featuring a 13” 120Hz high-refresh-rate screen and Intel’s most powerful integrated graphics, Iris Xe. Taking advantage of post-launch discounts that reduced some of the premium pricing, I decided to take the plunge and buy one.

Overall, I’m fairly satisfied with the device, but as expected from a Microsoft product, there are still some minor issues. However, as a Windows machine, software-related problems are often fixable with some hands-on effort.

Fix for Windows 11 Unable to Change Default File Opening Method

I encountered a strange issue recently—after upgrading to Windows 11, the option to change the default opening method for formats like .jpg, .png, etc., in the settings became grayed out and unusable. It was impossible to change the default image viewer, forcing the use of Windows’ default Photos app.

However, on another Windows 11 computer, this issue didn’t exist. After comparing the registry, I found that it wasn’t a Windows bug but rather a restriction intentionally added to the registry by a third-party image viewer when setting the default opening method (possibly to avoid bugs in older systems).

PS5 Vs. Xbox Series X

After the dream of “building a high-performance PC” gradually faded, I used my original budget to purchase a PS5 and an Xbox Series X. In media reviews, they are considered the most powerful consoles of this generation, both supporting HDMI 2.1 4K 120Hz and being quieter than their predecessors. However, after hands-on experience for a while, I found that while each has its unique strengths, they also come with their own issues.

The Most Powerful of This Generation —— PS5 and Xbox Series X — PS5 / Xbox Series X

Every gamer has different priorities, so this article will compare various aspects of the two consoles from as many perspectives as possible. Readers can focus on the sections that interest them.

This article was written in June 2021, and the situations mentioned may have changed in the future.

August 2021: Updated information on Xbox PC remote play and Xbox Series X system UI resolution to reflect features in beta testing and soon to be added.

September 2021: PS5 has added NVMe SSD expansion support via a firmware update.

March 2022: Sony has announced that PS5 will soon support VRR (Variable Refresh Rate).

Project SEKAI Game Analysis

Hearing that Hatsune Miku released a new mobile game, I skillfully opened the Play Store, downloaded, and ran it. The game, just as skillfully, popped up with a smooth animation: 「通信エラーが発生しました」(“A communication error has occurred.”) Well, Japanese games loves abusing SafetyNet, after all.

Swiping back, I added the game to the MagiskHide list. Cleared the data, opened the game again—and… “A communication error has occurred.” Huh? What’s going on? I double-checked the settings, cleared the data again, but the error persisted. Slowly, I recalled the fear of being dominated by Disney+ Widevine L1. Could this game also enforce SafetyNet Hardware-backed Key Attestation?