On Fri, Apr 20, 2007 at 04:52:04PM +0200, Daniele Arena wrote: > > >> I remember this because I had such a reload and it was during a period > >of heavy cosmic activity.. as the hardware had always been reliable and > >was reliable after this was beleived to be the cause > > > >We have also started to use this as the standard excuse. > >Up to now, people believe us... > > Well, there is some documentation on Cisco containing references to > cosmic rays and parity errors: > > http://www.cisco.com/en/US/products/hw/routers/ps341/products_tech_note09186a00800942e0.shtml > > Cisco 7200 Parity Error Fault Tree > > "As with all computer and networking devices, the NPE is susceptible > to the rare occurrence of parity errors in processor memory. Parity > errors may cause the system to reset and can be a transient Single > Event Upset (SEU or soft error) or can occur multiple times (often > referred to as hard errors) due to damaged hardware. SEUs or soft > errors are caused by "noise" most frequently due to high-energy > neutrons generated in the atmosphere by cosmic rays. For more > information on SEUs, refer to the Increasing Network Availability > page.
yup, thats the reference i was referring to.. we indeed had a single event upset on an NPE :) Steve