RSS 

How To: Upgrade a HA Pair (Part 3 of 3)

In this AskSupport How To video you will learn how to Upgrade a HA Pair (Part 3 of 3)

Tags: technical support netscaler how to
Views: 667
Rating: 5

Transcript : So, let’s step ahead. I’m going to upgrade the primary box. While this is upgrading, I’ll just point out one or two things here. If I go to the nsconfig directory, we can see here NS9.0. Right? This file here is basically a hard copy of the last config on 9.0. Right? When we do an upgrade between major versions, we keep a permanent copy of that. So this one never gets overwritten. We can see we have ns.conf.0, 1,2,3,4. Every time we click save config, it will write out a new file and increment these numbers. So you can see here by the time stamps, you can see when it’s been saved, the last date. Okay. So it just simply pushes them down a queue, like we can see as, oh, 17:42, 17:42, 17:10. This was the second most recent, the third most recent, and so on and so forth. So this is finished. I’m going to say no here just for the moment. And so bas…this is a file that we keep. If we downgrade to 9.0 from 9.1, we need to replace the ns.conf here, okay, with this file. Okay. We need to do that. So we would…you’d take a copy of this just for…you know, just as a keepsake, I suppose. And just cause you don’t want to…well, I’m a bit of a packrat that way. I don’t like to delete things outright. So I’d make a copy of this. And then you just use this command…well…yeah, you’d… Once you make a copy of ns.conf…cp ns.conf.9.1 backup, something like that, okay. You’d enter this type of command to backup the file, and then you would use this command here--9.0—to basically copy this file back to ns.conf. Okay? You restart the appliance after you’ve done the downgrade. The box will come up nice and clean, right, running the old 9.0 conf. What happens to the configuration if you’ve made any config changes from 9.1? I’m afraid they’re gone. We can’t really import those back to 9.0, in case there’s features that you’ve configured here which aren’t supported or aren’t, aren’t…that don’t exist yet in 9.0. So, here we are back. Our primary is here. Our ping replies are going. We’ve upgraded the primary. We have the option, if you want to…there is the option, if you want, just to test, for a short period of time you can run a force failover it. Okay. There is…that is an option. Do remember, though, that we are running a HA pair in two different modes. Okay? So we have one running 9.0, one running 9.1. Okay. So, if you do a force failover, traffic’s going to start passing suddenly using a different feature. Okay. So, just keep that in mind. So…sorry, using a different version, not feature, of course. So, one of the things we recommend we can do here, we run…take a look at the ns.conf. You might want to download this, make sure all your major Vservers are there. Once you’re happy with this, if you want to do a diff against the ns.conf 9.0, please feel free, just to have a look at any changes. Once you’re confident that the config on this…on the secondary box, you can simply reboot the primary. Okay. The other option, again, is to do a force failover, which we can run that for a short period of time. So, do a sho node. We can see here now Node 0 is up. Right? We just one…request time out while the switch between here and there sorts themselves out. It’s a couple of hops. And do a sho node. You can see that this is now up. Right? It’s now the new primary. And this box here is restarting. Production traffic still flowing. Okay? So all is good. Now, one thing we have to be wary of when we’ve done an upgrade. You want to use the config utility. We now have a new config utility version. This is for 9.0. We have to clear our Java caches. Okay? Because we do have these jar files which are present. So I go to Control Panel, go to Java, Settings, and I delete these here. This is to make sure that we don’t try to load our old configs. Then we get a little error that will tell us there is a version mismatch between the Java gooey that we have, that’s been downloaded to the hard disk cache and what the system is presenting us with. So let’s load up this page again. And now it’s loading up the new config, the new config utility. If you’re worried about maybe a corrupt install file, I’ll just bring this up now while we’re waiting for the systems to come back online. We do include in the releases a md5 hash. So, here we are here. This contains the hash. Right? What is this the hash of? This is the hash of the kernel. Okay? This basically is what get’s loaded, this file here. And that’s the most important file. Okay? This is what gets…this is what boots up…if this is corrupted, we’re in trouble, when we go to reboot. It’s not unrecoverable, by all means. We do have some good KB articles on how to get out of this. And that’s why we recommend putting the install files on the hard disk, because we can simply copy the previous one back. Okay? It is possible to recover from having a corrupt kernel. So, this has now come back up remote node here. We can see, because I’m connected to the serial console, I get all these messages. State is up. Okay? So, happy days. Let’s go to System. High Availability. Up and up. We have now upgraded our HA pair. We’re now both running 9.1. So, thanks so much for listening. I hope this is useful to you. If you have any questions, please don’t be afraid to use the link at the bottom of the page where you’re viewing this video, if you’re viewing it on Citrix TV, of course. Otherwise, please don’t hesitate to fire an e-mail on to our forums. If you go to support.citrix.com, you will see a link there for the support forums, and we’ll be happy to answer any questions you have there. So, thanks so much for watching, and have a nice day.