In the past couple of days, I've been paying closer attention to our linode web server because we got wind of a possible planned attack aimed at sites in our general area of business. I noticed there have been a few periods of time where Linode's graphs of the system are missing data. This snippet is from the daily traffic graph; that peak is only around 0.4MB/s:


It this a normal sort of glitch or something I should try to correlate with malicious activity? Can these graphs even be affected by anything running on the linode? It's pretty lightly loaded; daily peak around 35% CPU and the peaks on either side of those graph gaps were under 10%.

Not sure this would matter, but the linode is running on dallas670 where I've been ignoring a free upgrade for months 'cause I don't need it and am waiting for something to happen for which I do need to reboot.

Thanks for your thoughts,
Dave

P.S., I'm hoping this is just a normal bug in these graphs, which is why I put it in FR/BR here, but if any mod wants to move it (or tell me to delete/repost) to a different forum, just let me know!

I also see gaps like that on occasion. I don't think it's anything suspicious, just shows that the monitoring system failed to retrieve data (for whatever reason).

_________________
sleddog

Those graphs are supplied on a "best effort" basis, gaps happen on the odd occasion and are nothing to be worried about

Thank you both for the reassurance and confirmation!

To add another point, by my memory these graphs are generated by the host machine. So a compromise of your guest VPS wouldn't have any effect on generation of the graph (other than the malware's use of CPU, network, etc.). This is also why they don't show things like % disk usage, since that's not visible from the host.

This is correct. Although we are working to reduce the occurrences of these issues, gaps in the graphs on the "Dashboard" and "Graphs" tabs are simply the result of a hiccup in stats processing. They do not mean that your Linode was affected in any way, just that the statistics were not able to be processed. Only Longview graphs are based on the internals of your Linode.

- Jonathan

Some locations seem to be more prone to these "hiccups" than others.

My two linodes in Tokyo are showing 6 and 4 gaps in the last 24 hours, respectively. The combined duration of those gaps is more than one hour. That's no ordinary hiccup, it's a full-blown respiratory disorder

In the meantime, my other linode in Fremont is showing a perfectly continuous graph.