Matt, You mentioned "10 min for full HA convergence" which seems long. But then again, we've also seen a consistent issue where during an HA event the configs are reported as "out of sync" and the secondary controller has to reboot, sometimes more than once to re-sync.
My current theory is that very dynamic parts of the configs like rogue adhoc alerts should be left out of the controller XML sync check and this would enable faster HA pairing. Kitri Waterman -- Network Engineer (Wireless) University of Oregon On 2/19/15 11:58 AM, Williams, Matthew wrote: > > So far for us, I the benefits outweigh the risks. In our case, when > we failed one route engine the 8510s simply failed over to the HA box > and there was no perceivable degradation in the user experience. Our > issues with using Layer-2 for the HA only occurred if BOTH of our > upstream switches had a routing engine failure within the 10 minutes > it takes for the full HA convergence time. The odds of that happening > at the same time are extremely remote and would most likely indicate a > much larger networking issue that would trump a wireless outage. > > > > We chose to do the direct connection just to be extra safe. In fact, > the only reason we even found out about the routing engine issue was > because we replaced routing engines in each of our upstream switches > at roughly the same time. > > > > I don’t know how much testing you have done with the 8510s but we’ve > run them through some pretty good paces. > > > > Respectfully, > > > > Matthew Williams > > IT Manager, Wireless > > Kent State University > > Office: (330) 672-7246 > > Mobile: (330) 469-0445 > > > > *From:*The EDUCAUSE Wireless Issues Constituent Group Listserv > [mailto:WIRELESS-LAN@LISTSERV.EDUCAUSE.EDU] *On Behalf Of *Lee H Badman > *Sent:* Thursday, February 19, 2015 2:49 PM > *To:* WIRELESS-LAN@LISTSERV.EDUCAUSE.EDU > *Subject:* Re: [WIRELESS-LAN] Looking for testimonials- 8510 vs 5508 > WLC reliability > > > > I saw the bowing thing- that’s insane. It makes me curious about the > racks they are mounted in. > > > > To date, do you see the advantages of the 8510 as outweighing the > concerns? > > > > > > *From:*The EDUCAUSE Wireless Issues Constituent Group Listserv > [mailto:WIRELESS-LAN@LISTSERV.EDUCAUSE.EDU] *On Behalf Of *Williams, > Matthew > *Sent:* Thursday, February 19, 2015 2:46 PM > *To:* WIRELESS-LAN@LISTSERV.EDUCAUSE.EDU > <mailto:WIRELESS-LAN@LISTSERV.EDUCAUSE.EDU> > *Subject:* Re: [WIRELESS-LAN] Looking for testimonials- 8510 vs 5508 > WLC reliability > > > > Lee, > > We’re going through this as we speak. We’ve seen some issues with the > controllers physically bowing. We’ve also had issues with running HA > via Layer-2 when upstream routing engines/supervisor cards fail. Part > of the issue is that there is very limited keep alive timer control in > our version of code and the thresholds aren’t high enough to mitigate > the route engines switching over. Cisco recommends direct connecting > them, so we’ve resorted to using switches as media converters for the > direct connection. > > > > The good news is that 8.0.100 reintroduced timer controls that did > mitigate the failures when using Layer2 for the HA. The bad news is > that 8.0.100 caused watchdog failures in the 8510s. > > > > Respectfully, > > > > Matthew Williams > > IT Manager, Wireless > > Kent State University > > Office: (330) 672-7246 > > Mobile: (330) 469-0445 > > > > *From:*The EDUCAUSE Wireless Issues Constituent Group Listserv > [mailto:WIRELESS-LAN@LISTSERV.EDUCAUSE.EDU] *On Behalf Of *Lee H Badman > *Sent:* Thursday, February 19, 2015 2:35 PM > *To:* WIRELESS-LAN@LISTSERV.EDUCAUSE.EDU > <mailto:WIRELESS-LAN@LISTSERV.EDUCAUSE.EDU> > *Subject:* [WIRELESS-LAN] Looking for testimonials- 8510 vs 5508 WLC > reliability > > > > One more for the group: Having a large number of 5508s, I have an > interest in greatly simplifying the environment by moving to higher > capacity 8510s (zero interest in 5760s). > > > > I’m hoping to hear from those that have taken the 8510 plunge. For us, > outside of code issues, the 5508s have been solid hardware for us. > Would like to know whether current 8510 users find them to be reliable > as hardware, and whether the HA promises live up to the glossy. > > > > Thanks- > > > > Lee B. > > > > Lee Badman > > Wireless/Network Architect > > ITS, Syracuse University > > 315.443.3003 > > (Blog: http://wirednot.wordpress.com) > > > > > > > > ********** Participation and subscription information for this > EDUCAUSE Constituent Group discussion list can be found at > http://www.educause.edu/groups/. > > ********** Participation and subscription information for this > EDUCAUSE Constituent Group discussion list can be found at > http://www.educause.edu/groups/. > > ********** Participation and subscription information for this > EDUCAUSE Constituent Group discussion list can be found at > http://www.educause.edu/groups/. > > ********** Participation and subscription information for this > EDUCAUSE Constituent Group discussion list can be found at > http://www.educause.edu/groups/. > ********** Participation and subscription information for this EDUCAUSE Constituent Group discussion list can be found at http://www.educause.edu/groups/.
