John Mann's Weblog (on sng) | |||||
String around my finger
Index
Flavours
Links
Subscribe
Click to call me FWD# 61159 |
Mon, 18 Jul 2005 http://www.bbc.co.uk/bbc7/comedy/progpages/goons.shtml US Goon Show Archive www.goon.org http://www.thegoonshow.co.uk/ http://www.thegoonshow.co.uk/cds/index.html http://www.goonshow.org.uk/ Update 18-Jul-2005 Also stocked at shop.abc.net.au including The Goons - Last Goon Show of All on DVD Ross Khan (at Monash South Africa ) reports ATS doesn't address the issue of the lack of redundancy of the PSUs within the various pieces of equipment in the rack. Cisco offers a solution for externally powering switches, using the PWR675(?) external power supply, which can power up to 6 Cisco switches. When we did our new Core switch based on 2x Cisco 3750s, we acquired a PWR675 unit for each 3750 (using one powr port each) and then connected the switch's internal power supply to SupplyA and the external PWR675 input to SupplyB. This works really well under normal conditions, however there are 2 drawbacks: 1. - When power is restored, the switch doesn't switch back to the internal supply 2. - When running on the external supply and with power restored to the switch's internal supply, the switch is prone to random reboots (this observed behaviour is documented in the manual). In spite of these caveats, the presence of the PWR675 unit does improve the availability of the 3750 based cluster vs. the cluster running from only internal power supplies... It has to be said that Cisco don't recommend that the PWR675 be used in this configuration - we'll have to revisit this in the not-too-distant future... :-) Cisco might recommend 1 PWR675 to backup a stack of 2 switches. But I can'ty see why 1 PWR675 per switch dould be un-recommended. It gives power feed resilience, as well as power-supply resilience. |
||||