The blog post details troubleshooting a Hetzner server experiencing random reboots. The author initially suspected power issues, utilizing powerstat to monitor power consumption and sensors to check temperature readings, but these revealed no anomalies. Ultimately, dmidecode identified a faulty RAM module, which, after replacement, resolved the instability. The post highlights the importance of systematic hardware diagnostics when dealing with seemingly inexplicable server issues, emphasizing the usefulness of these specific tools for identifying the root cause.
The blog post "Debugging Hetzner: Uncovering failures with powerstat, sensors, and dmidecode" details a systematic approach to troubleshooting hardware issues on Hetzner dedicated servers, specifically focusing on identifying the root cause of seemingly random reboots. The author emphasizes the importance of proactive monitoring and diagnosis, especially given the limited support options available with Hetzner's Rescue System.
The post begins by highlighting the limitations of relying solely on Hetzner's provided information, such as IPMI logs, which might not always pinpoint the exact hardware culprit. It then introduces a trio of tools – powerstat, sensors, and dmidecode – and explains how they can be utilized for deeper investigation.
powerstat is presented as a crucial tool for monitoring power consumption and identifying potential power delivery problems. The author explains that erratic power readings, fluctuations outside of expected ranges, or complete drops can indicate faulty power supplies, cabling, or even issues within the server's power distribution components. The post suggests comparing powerstat readings under different load conditions to establish a baseline and identify deviations.
Next, the article focuses on sensors, a utility that reads hardware sensor data. This includes readings from temperature sensors, fan speeds, and voltage regulators. By monitoring these values, one can detect overheating components, failing fans, or voltage instability. The author advises checking these readings both at idle and under load, as some problems might only manifest under stress. The post also cautions that interpreting sensor readings can require familiarity with the specific hardware being used and recommends cross-referencing readings with the server's specifications.
Finally, the post discusses dmidecode, a tool that retrieves Desktop Management Interface (DMI) information from the system's BIOS. This information can provide valuable details about the server's hardware components, such as the model, manufacturer, and serial numbers. The author explains how this information can be useful for identifying specific hardware revisions that might be known to have issues, and for contacting Hetzner support with precise information when requesting replacement parts or further investigation.
The blog post concludes by reiterating the importance of proactive monitoring and utilizing these tools to gather evidence before contacting Hetzner support. By presenting a clear methodology and explaining the utility of each tool, the author empowers users to diagnose hardware problems more effectively, leading to quicker resolution times and minimizing downtime on their Hetzner dedicated servers. The post also underscores the importance of understanding server hardware and using available tools to bridge the gap between limited support and complex hardware issues.
Summary of Comments ( 36 )
https://news.ycombinator.com/item?id=43101430
The Hacker News comments generally praise the author's detailed approach to debugging hardware issues, particularly appreciating the use of readily available tools like
ipmitoolanddmidecode. Several commenters share similar experiences with Hetzner, mentioning frequent hardware failures, especially with older hardware. Some discuss the complexities of diagnosing such issues, highlighting the challenges of distinguishing between software and hardware problems. One commenter suggests Hetzner's older hardware might be the root cause of the instability, while another offers advice on using dedicated IPMI hardware for better remote management. The thread also touches on the pros and cons of Hetzner's pricing compared to its reliability, with some feeling the price doesn't justify the frequency of issues. A few commenters question the author's conclusion about PSU failure, suggesting other potential culprits like RAM or motherboard issues.The Hacker News post "Debugging Hetzner: Uncovering failures with powerstat, sensors, and dmidecode" has generated several comments discussing the author's experience debugging hardware issues with a Hetzner server.
Several commenters shared their own experiences and perspectives on Hetzner's hardware and support. One commenter mentioned their generally positive experience with Hetzner's hardware reliability, contrasting it with the author's described issues. Another user questioned the efficacy of using
powerstatfor diagnosing power issues, suggesting alternative tools or methods. They also pointed out the potential for IPMI access being more helpful in such situations.A significant part of the discussion revolves around Hetzner's practice of using refurbished hardware. Some commenters speculated that the author's problems stemmed from this practice, while others defended Hetzner, arguing that refurbished hardware can be a cost-effective and environmentally friendly option. One commenter shared a personal anecdote of receiving a server with a failed RAID controller, highlighting the potential risks of refurbished hardware. Another commenter suggested that while Hetzner does use refurbished hardware, the quality and reliability can vary, and that their dedicated server offerings are often a good value despite this.
One commenter expressed surprise at the author's decision to troubleshoot the hardware themselves, suggesting that contacting Hetzner support would have been a more efficient approach. This prompted further discussion about the trade-offs between self-troubleshooting and relying on support, with some users expressing a preference for maintaining control over their own hardware.
There was also a brief discussion about the specific tools mentioned in the article. One commenter questioned the usefulness of
dmidecodein this particular scenario, while another mentioned the importance of having out-of-band management access like IPMI for debugging hardware remotely.Overall, the comments section presents a mixed bag of perspectives on Hetzner's hardware and support. While some users expressed concerns about the reliability of refurbished hardware, others defended Hetzner's practices and shared positive experiences. The discussion also touched upon broader topics such as the value of self-troubleshooting versus relying on support, and the importance of having appropriate tools for remote hardware debugging.