I am seeing the following errors in the Tor log: [...] Feb 28 04:54:43.008 [notice] Your system clock just jumped 4398 seconds backward; assuming established circuits no longer work. Feb 28 04:54:46.020 [notice] Your system clock just jumped 4399 seconds forward; assuming established circuits no longer work. [...]
I was having the same exact problem on Debian which was running on Xen. Removed ntp as the ISP:'s admin recommended, that did not help. Then they moved my virtual machine to another host and everything was fine for a while. As for now the problem is occuring about once a week, two or three error messages.
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