GREAT question, I'd sure like to here the answer. I concur on the more blades than normal having problems and have wondered about a manufacturing location change as well as this backdoor current question.
Larry Puckette Senior Network Analyst Temple Inland/Austin Data Center 512/434-1838 [EMAIL PROTECTED] Where the only idol is money and power, there is no hope for integrity. -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Sent: Friday, July 11, 2003 9:47 AM To: [EMAIL PROTECTED] Subject: OT: electrical issues with switches [7:72151] This is completely off topic and, in my case, of an operational nature, so I need to apologize in advance. Unless there is some expressed interest please respond to me privately if you would, thanks. We have suffered over the last couple of years what I would consider an unusually high number of blade failures in various switches (from several vendors including Extreme and Cisco). They have the earmarks of an electrical problem, that is, supplied current spiking and valleying. For instance, where I am located - Northern Virginia - we had some major storms move through last night. This morning I had two blade failures in two separate closets. These closets all have UPS units (usually more than one) and the switches, all of which have dual power supplies, and are split with one power supply going to one UPS, the other to another UPS. Granted both are in the same room and usually plugged into the same circuit. Seemingly this would eliminate, or at least mitigate, the bulk of any electrical fluctuations in the closets. The UPS's have been tested with various diagnostic tools and they appear to check out fine. My question is this. The failures seem to occur more often on densely populated blades (isn't that always the case?). Many people in the building leave their PC's on at night. When the power goes out in this building, the PCs in most areas will also power down. When power is restored, even if it just flickers, all these machines will boot at the same time. Is there any chance that this surge - if there is one - of current coming from the rebooted PC NIC cards could cause these issues? Or is there even a current that flows back from the NIC's (it would seem logical, but I am not an EE). I do realize that I may be grasping at straws. Any thoughts, and again I apologize for the off topic content. There are many bright folks in this group so I thought I would ask. Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=72154&t=72151 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]