Transcript

Introduction

>> Dave:  Welcome, everyone. I appreciate you joining us today for another SkillBuilders’ webinar. 

 

Today’s webinar is entitled RAC and Grid Infrastructure: What Every DBA Needs To Know. 

 

My name is Dave Anderson and today our instructor, our presenter will be John Watson. 

 

I’d like to tell you a little bit more about John and I. 

 

John is SkillBuilders’ Director of Oracle Database Services. So what John does is DBA work for our customers. It involves work contracts, performance tuning, Data Guard implementations, RAC implementations, teaching, and just a whole host of Oracle Database related things. Half of which I don’t even understand, but he does a wonderful job at it. 

 

John is an Oracle Certified Master with 8 certifications including the 11g RAC and Grid Infrastructure Administration. You may have heard of John before because he has authored many, many textbooks including the Oracle Press Exam Guides.

 

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Transcript

Why All Administrators Need to Know Grid Infrastructure

 

>> John:  The subject I want to cover today is the absolute minimal level of knowledge that I strongly believe all administrators, system administrators as well as database administrators need to know. 

 

I want to cover the basic usage of Grid Infrastructure, the minimum that all administrators need to know. And I really do want to emphasize that it isn’t just database administration, it’s system administration. It’s even network administrators, storage administrators, all types of administrators, perhaps even payroll administrators. All types of administrators in a technical environment really do need to study Grid Infrastructure. 

 

Why? It’s because in the Oracle environment, the database administration and system administration roles are converging. The domains are merging together and all organizations now need to make a decision about where these functions actually should reside. 

 

[pause]

 

From my own experience, it’s true to say that when implementing Grid Infrastructure most sites, the majority of sites add responsibilities to the database administration domain. But that isn’t always true. I’ve worked at sites, particularly sites where a Grid Infrastructure was replacing third party products such as Veritas Clusterware or IBM HACMP where the grid infrastructure administration is in fact given to the system administrators. 

 

[pause]

 

There’s quite a lot of sense to that. What is Grid Infrastructure? It’s techniques for managing the network, managing storage, managing the clusterware, and that’s traditionally always been system administration work. But because the product comes from Oracle, probably the majority of sites it does tends to be the database administrators have to extend their role into the system administration domain. 

 

[pause]

 

Whoever has the job of administering Grid Infrastructure, whether it’s the DBA or the SA, both sides need to understand it. 

 

[pause]

 

I also want to emphasize that this is not about RAC. Of course with Grid Infrastructure is the platform on which RAC’s real application cluster databases will run in most circumstances. But most of what I’m going to cover in this short session is also applicable to a single instance databases and a lot of it is in fact applicable to applications that have nothing to do with databases at all. 

 

This is because Grid Infrastructure is a lot more than support services for RAC. It is indeed fully functional general purpose clusterware. 

 

[pause]

 

The three major topics I’m going to go through are just some of the facilities that Grid Infrastructure provides for network administration. Some of the facilities are provided for storage administration. And if we have time, I want to run through some of the high availability capabilities that are provided by the clusterware part of Grid Infrastructure. 

 

[pause]

 

First, network management.

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Transcript

Intro to Network Administration with Grid Infrastructure

>> John:  In the arena of network management, I need to make sure that we are all – as if we’re on the same page with the manual. So for those of you who are already network administrators please bear with me. But for those of you who are not, you must remember that every IP address in the world will either be static or dynamic. 

 

Static addresses, one host name always results to the same address. A dynamic address, the host name could be assigned to any address at any one moment and the addresses will presumably have been assigned on the fly by DHCP server. 

 

[pause]

 

Addresses then may be static or dynamic. 

 

[pause]

 

Secondly, addresses will be fixed or virtual. A fixed address is tied to one physical address, one particular network card that always responds to that particular IP address. 

 

[pause]

 

A virtual address can float around from machine to machine, from network card to network card. So every address we have will be either static or dynamic, fixed or virtual. 

 

Grid Infrastructure is working towards the use of dynamic virtual addresses. Why? Because dynamic virtual addresses give you the flexibility you need to manage changing topologies. In an ideal world, all addresses will be dynamic and virtual. 

 

[pause]

 

Why? So the network can respond automatically to any changes and users will not be aware of the changes. 

 

[pause]

 

What could these changes be? They could be relocating machines, they could be adding servers, removing servers, consolidating servers, perhaps changing from physical servers to a virtualized environment, even moving new environments from local physical servers to the cloud. 

 

[pause]

 

Ideally, the network will make such changes transparent to the applications and the users. Your network management facilities need to ensure that the host names, the virtual host names will be assigned to virtual addresses that can float about to wherever they how come to be needed either a response to a deliberate reconfiguration of the topology or of course because of response to failures. 

 

[pause]

 

Historically, this was done with third party products. But as an Oracle person I call them third party products that never done with operating system facilities. 

 

But now Grid Infrastructure can handle all of these. The integration with DHCP there is a certain amount but a very minimal amount of DNS configuration required and when you are assigning addresses dynamically – as always the issue – how do you tell your clients what address are particular host name actually is at this particular moment. 

 

[pause]

 

Normally, historically, that would’ve been done with DNS. Now Grid Infrastructure does that. What is called the GNS ñ the Grid Naming Service which works with DNS. 

 

[pause]

 

And of course Grid Infrastructure handles failover – automatic failover or manual.

 

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Transcript

Demonstration – Network Administration with Grid Infrastructure

>> John:  How does it do it? Well, take an example, very simple example here. 

 

I’m working on a very straightforward cluster at this point. I’m using Grid Infrastructure version 12.1 which is the latest beta. Incidentally, I happen to be using 12.1 because that’s what I have installed, but I’m trying to avoid anything that is 12c specific and stick purely to facilities available on your 11g or even 10g systems. 

 

This is a perfectly normal Grid Infrastructure installed. And if you look at a topology of the cluster it is just a simple two node cluster, two node gold 1 and gold 2. 

 

[pause]

 

Now, if I were to generate a new IP address – as a system administrator, I want to assign a new IP address and create a new host name. I can do it now with just a single command. 

 

Add VIP. There’s a bit more going on in the background such as specifying the location of the scripts. 

 

[pause]

 

That will have created it. They need to start up at VIP. So we use CRC PL utility, start resource. 

 

[pause]

 

Which resource? That’s IP address and host name. Address created. 

 

It happens to have started on gold 2. When I created it, just for that very simple call there, I didn’t specify anything about where I wanted it. I was relying purely on defaults and Grid Infrastructure in its wisdom has decided to start it on that machine. But I don’t need to know that. Does it actually work? 

 

Well, can I ping John VIP and the goldcluster.example.com. and it’s responding. So on the fly, I have created an IP address, a host name, and the name written usually is working correctly. 

 

Oracle has worked out a Grid Infrastructure as a sign that address through that name on the fly and my end users would have no reason to know where it actually is. Now, the proof by the way, the address is at 5691. If we go here, we can see on gold 2.

 

[pause]

 

There it is. It’s come up as the third virtual address on network card ETH0. 

 

[pause]

 

What if I want to relocate it? No problem, no problem at all. I won’t crash the machine. That would have been right now. I want to use it later on. But if I crash the machine, Grid Infrastructure would identify that and the VIP would then failover automatically. 

 

But if I wish I can start to do it manually, the syntax. 

 

[pause]

 

We relocate the resource, the source is currently on gold 2 and I want to move it to the node gold 1. 

 

[pause]

 

So manually we’ll relocate it. 

 

[pause]

 

Do my end users notice any change? 

 

[pause]

 

Of course they don’t, it’s still responding. But physically, it will now no longer on this machine. If we look at this we see. 

 

[pause]

 

Yes, it’s gone. It’s no longer there. 

 

[pause]

 

And it will now come up on this machine instead. 

 

[pause]

 

There it is, going to pop up on gold 1. 

 

Grid Infrastructure can now handle all these facilities that would previously have been the domain of the system administrators. I’ll just stop the resource now, crsctl stop resource John VIP. 

 

[pause]

 

If I try to ping it now, 

 

[pause]

 

it still resolves and that will be because the DNS will have cached the address. It’s going to work for a while. One normally would configure caching of addresses to handle temporary problems perhaps in some temporary issue with the DNS server itself, but it no longer response because I’ve stopped it. 

 

[pause]

 

To do that without Grid Infrastructure, it can be a dreadful process of updating. To start an address what you have to do? You have to find the address somewhere. I have to get it from the DHCP server, you then have to start it up, you have to propagate the name and the address to your DNS server. Maybe you have to update vast numbers of host files. It’s a pretty dreadful process, which I’ve done just with three or four commands. 

 

[pause]

 

I should say at this point but it’s beyond the scope of this very short session, unfortunately we don’t have time, what will normally go on to define a dependency between the addresses and the application. Now having my address failover from one machine to another isn’t much use unless the application it services also fails over, and that we could do. We could build dependencies between say one virtual host name address on one service. Such this logical name like www.skillbuilders.com would failover from one machine to another and the Apache Web Listener would also failover as well.

 

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Transcript

Network Administration with Grid Infrastructure Q & A

coming soon…

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Transcript

Grid Infrastructure Storage Management, ACFS, the Cloud File System

>> John:  To proceed to my next major topic. Network management can now just be brought within the Grid Infrastructure environment. But in some ways even more powerful than that is the storage capability. Storage as well can move into Grid Infrastructure domain. 

 

[pause]

 

When we talk about storage, we have what’s called – Oracle now calls it the Cloud File System, the Cloud FS, ACFS previously known as the ASM Clustered File System. ACFS or now it’s being remarketed the Cloud File System. 

 

[pause]

 

ACFS in some ways it’s a file system like any other. But it does have some very nice features. It can do replication, snapshots, and encryption. Their application really does work across a wide area of network. So that we write and we can use it as a regular file systems to our word processing documents, our Excel spreadsheets, anything you like, scales limit must be of course on one site automatically replicate to another site. 

 

[pause]

 

The snapshot capability that’s very similar. The technology is very similar in concepts to Solaris ZFS snaphots. ACFS will allow you to create a snapshot up to – several dozen snapshots are possible and then it will give you a really consistent copy of the file system with an efficient creation mechanism based on copy on update. Very similar to how ZFS works. 

 

It also with the latest release has encryption. It does conform to the various federal [01:48 inaudible] required for encrypting data on disc, transparently of course. The encryption happens to and from the path to disc. So if your data is protected on disc, even if the machines are discarded, the data is still protected. But because it’s transparent, it will approve the applications and see the data. 

 

These are nice facilities. So when I say that ACFS in some ways is a file system like any other, yes. But it can do these things you cannot do for example with EXT3 for instance or NTFS. NTFS can do replication now, but I don’t think you can do some of the other capabilities. 

 

[pause]

 

Also of course Grid Infrastructure storage provides storage for your databases and that’s ASM which has been around since 10g release 1. It was a bit unreliable with 10g release 1 but it has been around for many, many years now. I do not want to spend time unless anyone’s particularly interested and chat here in the message. I don’t particularly want to spend time talking about using Grid Infrastructure for storing database files. We have had a separate series of webinars to deal with that. 

 

So just in summary, of course Grid Infrastructure is used for storing database files and the storage is extremely fast and reliable. And [03:00 inaudible] to prove to you why it outperforms third party products, should any of you be interested. 

 

Speaking of replacing third party products, how do we position Grid Infrastructure? 

 

Just as with the network capabilities, the network capabilities didn’t do anything that you couldn’t have done before. But maybe that is it in a more convenient fashion, maybe they can do it more cheaply. It’s the same with storage. Third party products can do what ATFS can do. 

 

[pause]

 

Plus ATFS can also replace third party products. It can replace cluster file systems. It can replace network file systems. All you file service, your NFS servers, your Windows SMB or samba file servers – we can replace all of those. It can replace hardware RAID. Many large environments will of course be using samba storage and your underlying storage will be striped to mirror [03:56 inaudible] coming from some sort of storage array. 

 

Grid Infrastructure can do the striping and mirroring for you. The advice on this is somewhat indeterminate and very much site specific. I could say Grid Infrastructure will replace your hardware RAID. At most sites I’ll be saying the Grid Infrastructure will work with it. If you already have a SAN capable of doing striping and mirroring will allow Grid Infrastructure on top and that double layer striping can give you fantastic performance. 

 

So it can replace RAID or work with RAID. 

 

[pause]

 

It becomes an alternative then to your SAN and network attached storage and so it can replace [04:38 inaudible] or NFS sharing mechanisms. For network attached storage, it can replace the RAID systems you have in the background if you wish to. And it may indeed give you cost savings because of that. That of course would require a certain amount of investigation. We couldn’t guarantee that.

 

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Transcript

Grid Infrastructure Licensing Tips

>> Dave:  Just a couple of questions about Grid Infrastructure storages that’s separately licensed.

 

[pause]

 

>> John:  Oh gosh. If I were a salesman, I will be rich. This is one of the more confusing aspects at the moment. 

 

When the Grid Infrastructure storage – no. Let me take a step back. 

 

[pause]

 

Grid Infrastructure storage for ASM is not separately licensed. That’s included with any database license you may have. Standard Edition, Enterprise Edition – they all have including the database storage license. 

 

[pause]

 

ACFS when it was first released with 11.2, 11.2.01 it was included. However, it became extremely popular for a very good reason and Oracle has decided to backtrack a bit on the bundle licensing for ACFS. 

 

I do now see that when it’s [01:04 inaudible] cloud file system, there may be – depending on what you’re doing – there may be licensing implications. But I’m afraid I’m not enough of any expert on licensing to then get further on that at the moment. 

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Demonstration: ACFS, Cloud File System, Storage Management

>> John:  Here’s some CMD utility. Really to make system administrators feel happy with the Oracle environment, Oracle provides a tool that looks a bit like Linux or Unix. We have Unix commands so we have a kind of Unix interface. I’m deliberately using this rather than the SQL Plus interface that will be more familiar to database administrators. 

 

We have a Unix type interface. What I need to do to create a new file system, I use the command – I shall I copy here – vol create. I create a volume. This is the equivalent of creating a logical volume in a physical volume. My physical volume is called a group called ATFSv1. I’m creating a logical volume called vol1 of 256 megabytes. 

 

[pause]

 

I’ve created a logical volume here and the moment I created the vol create command, we see a device driver generated in /dev/asm and there’s my device driver. That just created a logical volume of 256 megabytes. 

 

[pause]

 

What do I do with that logical volume? We know what to do with logical volumes, we format them with file systems. In NKFS I could use – type EXT3. I could even use -type NTFS. At this point this is just a device driver like any other. I shall of course use ACFS because I want to get the ACFS capabilities. So, we create a file system with a perfectly normal NKFS command and that’s formatted a very little, a very small file system. 

 

What do we do next? We mount it. 

 

[pause]

 

Type “ACFS” and I would mount the device /dev/NNT/asm on say /NNT. DF [02:23 inaudible]. There it is. There’s my little 256 megabytes volume file system mounted and that is a file system like any other. 

 

[pause]

 

It’s like a file system like any other file system. But it happens to be managed and controlled by Grid Infrastructure. 

 

[pause]

 

This is a truly clustered file system. And I got trouble as pointed out with my other nodes, I can’t demonstrate the clusterability right now. But it’s clusterable, which many files systems such as EXT3 are not. And I can use it for anything I want. In that previous webinar that Dave just referred to, I demonstrated the snapshots and replication capabilities. 

 

[pause]

 

Now I just want to point out that ACFS ñ the file system in ACFS mounted file system is depending on the underlying storage it stripes mirrored plus be striped to mirrored twice. If the underlying storage cannot do striping and mirroring, ACFS will do it for you giving an equivalent to RAID 10 equivalent performance reliability. 

 

If you have underlying storage that can stripe itself then the performance will be even higher because that multiple levels of striping would use your SAN to stripe volumes and ACFS will then stripe files which is an extent base file system. 

 

So what’s the end result? It can replace third party products such as Veritas Cluster file system, Red Hat Global File System and of course it can replace all your file servers.

 

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Transcript

High Availability with Oracle Grid Infrastructure

>> John:  The next topic I wanted to cover is to do with high availability. This is where we move on to the Clusterware capabilities, how we can have services failover from one machine to another. 

 

[pause]

 

Now, in the database itself, we’ve had service failover between instances for some time. It first appeared back with version 9 but with version 9a, it was all manual. It became much better of course with version 10g, the automation came in. and with 11g, even more automation still.

 

[pause]

 

Grid infrastructure with 11.2 introduces the possibility of database or instance failover between nodes. We can actually have a database failover from one computer to another. That’s the sort of capability that’s previously one would probably would have to use HP Serviceguard or perhaps IBM HACMP to get some sort of equivalent functionality. 

 

Grid infrastructure can failover a database from one machine to another. Even slight problems with this cluster – I just have to hope that this will actually function. You’ll never know. We shall see.

 

Now, what I do want to do is demonstrate the database failing over if I can. The technique is to create what we call the server pool. That’s how we pool.

 

[pause]

 

So the detail of this, we can start these subsequently. Create a server pool and then when you need to assign your database to the pool – so I connect to my database home. I pre-created a database by the way. I created a database in advance and then registered the database with Grid Infrastructure. 

 

[pause]

 

So I’m adding the database to the Grid Infrastructure and registering it, and I’m assigning it to this pool – Rdb pool – that I created earlier. So, a pool of servers.

 

How big is your pool going to be? If own a site with 50 computers and you clustered all off, you probably wouldn’t put all 50 into one pool. You might have one pool for your production servers, one pool for your development servers, one pool for your test servers, and so on. But I only have only two nodes here. So I’ve created a small pool (Rdb pool) and I put both my nodes into it. Then I assign my database to the pool. 

 

[pause]

 

Add the database to the pool, but the pool has a couple of extra switches here. The pool has a name, Rdb pool minus L1 minus U1. That’s an instruction to the infrastructure, L at least, telling Grid Infrastructure to activate at least one server in this pool and activate up to one server in this pool, which is a long winding way of telling Grid Infrastructure, “I want one active machine in this pool.”

 

[pause]

 

Which will that machine be? One of those two. 

 

[pause]

 

Now I’ll start up the database.

 

[pause]

 

SRVCTL start database. 

 

[pause]

 

Start the database called Rdb as I corrected earlier.

 

I have no idea on which machine that database is going to start. I really do not know. Grid Infrastructure would follow its own load-balancing algorithms and start up the database on one of the machines that is in that pool. Only one because of the way I configure that.

 

[pause]

 

Now where has it in fact started – I could control it of course but I’m relying purely on trusting Uncle Oracle at this point.

 

[pause]

 

Status database minus DRBB and it has in fact started on the node IN1. I didn’t know that, but that’s where Oracle has chosen. Your Grid Infrastructure has chosen to start it. 

 

[pause]

 

There it is. Well, how do we failover to another machine? What’s the most brutal way to failover you can think of? I shall cause a problem. The problem I shall cause. I’ll just reboot the box. I need to do it anyway since this is the one way. 

 

[pause]

 

My kernel module is running. So I’ll shut down.

 

[pause]

 

I kill that machine. Just reboot it. Gone. Right.

 

[pause]

 

That will of course have terminated the instance. But Grid Infrastructure should pick that up pretty quickly and within a few seconds, minutes at most, it thinks it’s still running but of course it’s not running in this machine IN1 because machine IN1 no longer exists. It was rebooted at no on certain terms. 

 

[pause]

 

Pretty soon, Grid Infrastructure will pick that up and restart it. This is the sort of thing you could do with third party products – HP Serviceguard, IBM HACMP, Veritas Clusterware – any sort of system that will monitor what’s going on. Identify the fact that it’s not running on node 1. It’s not running on node IN2 either. But it will be soon. If we see, if it started up already RAC Rdb…

 

[pause]

 

It’s come up already. It’s already come up.

 

I didn’t time it but that’s probably less than a minute. So in less than a minute, the entire database failed over to another machine, which is pretty fantastic. Given the Grid Infrastructure cluster storage as well, the way we’re building dependencies, the disc groups contain the data of that database instance needs would also be remounted on the data machine it failed over to. Very nice indeed.

 

[pause]

 

>>Dave:  Very cool, John. Very cool. A couple of questions in the queue – is this a good time? 

 

>>John:  Yes, sure.

 

>>Dave:  One question is if the database is active during that failover, what about the current transactions? Are they lost?

 

[pause]

 

>>John:  That takes us onto the next aspect. A very timely question. That takes us on really to the next part of what I was going to talk about which is the fault tolerance from the client side. I’ve used as viewed by the client.

 

[pause]

 

I might as well show you now actually. If we look at what we call services, srv ctl, if I want to add a service, when we define a database service, we can define session failover. This is actually my 12c environment. 

 

When we can configure session failover to none and, in that case, all sessions against the failed instance or failed node would die. I won’t have to reestablish manually. We can have the session failover but only work in progress would go or we can have select statement failover, meaning that a session is logged onto the instance. The machine or the instance fails, the session fails over. 

 

If it is in the middle of a select statement, the session will appear to continue. You can continue to fetch with your cursor. That’s as far as we can go with version 10 and version 11. 

 

If you’re in a transaction as the question was, with version 12c, we can have the transaction failover as well. But I’m afraid up [08:03 inaudible] version 11, the best we can do for you is have a session failover and select failover. Transactions will be rolled back with the current release but that will change when we get the opportunity to take you on to the next release.

 

[pause]

 

>>Dave:  Very, very cool, John. 

 

[pause]

 

I think the last one for this, what if an application needs a virtual IP and a file system? Can you link them?

 

>>John:  Yes, we can. We can build independencies all the way. Let me show you that.

 

[pause]

 

I may be able to build up an example. What I have here for example, the way the dependencies work, yes, I’ll go through a listener and [08:51 inaudible] talking about scan single client access name. If I look at how my listener is configured

 

[pause]

 

Minus P to get the complete page of details, there’s a device, a service called ora.LISTENER_SCAN1.lsnr. What is it? It’s a scan listener. It’s a database listener. It has a particular purpose. It’s a database listener that services the single client access name.

 

[pause]

 

There’s the [09:24 inaudible], I mentioned earlier. But down here, we see [09:29 inaudible] properties. Here’s some of the fault tolerance stuff by the way. It auto starts. How many do we want and so on? How often do we check that it’s actually working? What to do with failovers? We don’t delay at all. We failover immediately. 

 

[pause]

 

But down here we see the dependencies. So we can build in dependencies between registered resources and we have here that my database scan listener has a hard dependency on that. That’s a VIP. Hard, meaning if that virtual IP address is not running, we cannot start the listener. That’s fair enough. The listener needs an address on which to listen.

 

[pause]

 

Then we see a clever part here, a pullup. A pullup dependency means we try to start this process, the scan listener and the VIP is not running, we will start it. 

 

[pause]

 

So you can build in as many dependencies as you like with all the registered resources. In the case of a database, I don’t have a database registered here. We were building a dependency on say certain file systems and on certain listeners as well. Just start one on a particular machine and that will pull up all the other resources, not the appropriate file system that’s required. 

 

 

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SQL Net Listening Architecture and SCAN

>> John:  The SQL Net Listening Architecture we get with grid infrastructure. It’s a two tier listening structure. 

 

There’s this thing known as the SCAN. The SCAN stands for single client access name. It’s one name resulting to three addresses. The idea of the single client access name is it’s a single, stable name that’s used by all users. 

 

In this particular case, the single client access name that I created – well, if I do nslookup of – it was called goldcluster-scan.goldcluster.example.com. That’s the name that I created as my single client access name. It’s the name that all clients are meant to use, the single name to use by the clients.

 

It resolves the three addresses, DHCP-assigned addresses. Three addresses the fault tolerance. These addresses will be brought up on one machine or another. 

 

The Grid Infrastructure of course will decide. I can see right now my three SCAN VIPs. One of them is on gold2, two of them are on gold1. So they get distributed across the cluster. 

 

[pause]

 

On each of those listening addresses, we start a SCAN listener, a database listener at that point. Then the purpose of the SCAN then, it’s a stable name – a stable name that all users use. So whenever a client uses a connect string, it will ask for the SCAN. The SCAN will resolve to one of those three highly available addresses that will failover from one node to another. And then the SCAN listener performs redirection to a node listener. The node listener is what will actually connect you to a database itself. 

 

Looking at my environment here, I go to say 

 

[pause]

 

Where I have my database running. 

 

[pause]

 

This was the cluster where I assigned my server – my database to a server pool. I crashed one machine and resolved database failover. At this point I really have absolutely no idea as an end-user where that database actually is. But that doesn’t matter. Because of the single client access name, the SCAN, I can issue like normal connect string to connect the system manager. 

 

The SCAN name at incluster-scan.incluster.example.com. Now it’s on port 1521. It’s on default. The database service is Rdb. 

 

[pause]

 

I have no idea what that thing actually is. But it worked.

 

[pause]

 

So what happened in that flow? Well, that connect string, that was resolved by the DNS into one of three addresses. There are addresses being DHCP-assigned virtual addresses. But the DNS was updated by Grid Infrastructure. So that actually worked.

 

[pause]

 

Then having contacted the SCAN listener on one of those three highly available addresses, Grid Infrastructure took it a step further and said, “What do you actually want?” You want something called Rdb and connected me to the appropriate instance wherever it happened to be. But I really didn’t know it was all completely automated.

 

That’s the beauty of it. If we configure a session that is automated, if we configure the session failover, it can be transparent to the clients. As I mentioned, the response to that earlier question, with the current release, transactions cannot failover. So they would have to be – they will be rolled back. Your application software would have to handle that.

 

But the session itself will be failover automatically. That will work not just for RAC. It will work for single instance databases. As I demonstrated, it will work for failover from primary to stand by your Data Guard environment. The listening architecture is an important part of this.     

 

 

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Transcript

Conclusion: Planning for Oracle 11g / 12c Grid Infrastructure

>> John:  The conclusion I want to come to, Oracle is moving everything to Grid Infrastructure. Oracle is really pushing it. And you can move not just your databases but many applications as well. You can use Grid Infrastructure to support your email servers, your web servers, everything. It requires storage and networking capabilities. 

 

[pause]

 

That’s why we see the domains are merging. And everyone really does need to start studying Grid Infrastructure and start studying it now. Because if you’re not using it now, I think you’re going to be using it in the very near future. So what I would advise everyone to do is start reassessing your environment and see what you’re using. What third party products are you using? What are your requirements for fault tolerance [00:54 inaudible] and see how Grid Infrastructure could fit in to that environment. What components could you use? What existing products could you replace? And how will Grid Infrastructure work with it? 

 

You need to start planning for this now. I strongly believe that. And with that I pass you back to Dave.

 

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