1 00:00:00,000 --> 00:00:17,800 Hey everyone and welcome back. So in this skill right here, what we're going to be focusing 2 00:00:17,800 --> 00:00:26,320 on is something called NFS. This is the network file system. And the real emphasis here is 3 00:00:26,320 --> 00:00:33,520 on that letter N network. This is really what the crux of this topic is all about. Now if you 4 00:00:33,520 --> 00:00:40,399 recall from the previous skill, we happen to talk about SAMBA. Now SAMBA was all about being able 5 00:00:40,399 --> 00:00:46,400 to share out different things such as printers or particular files and folders. And when we talk 6 00:00:46,400 --> 00:00:54,560 about NFS, there is some overlap, some similarity here, and that ultimately we are sharing resources, 7 00:00:54,640 --> 00:01:01,440 but we're not sharing the same things or in the same way as we would via a SAMBA server. So like I 8 00:01:01,440 --> 00:01:08,640 say, SAMBA, we are sharing out printers and folders and files with respect to NFS. What we are 9 00:01:08,640 --> 00:01:15,680 actually sharing is a file system itself. And how are we sharing this? We're sharing it via the 10 00:01:15,680 --> 00:01:22,079 network IE to other computers that we can connect to. So this really is the crucial difference 11 00:01:22,079 --> 00:01:27,200 when talking about NFS. It's actually that file system that is going to be mounted and going to 12 00:01:27,200 --> 00:01:33,920 be shared with other people so that they can use that just like it was a local file system on their 13 00:01:33,920 --> 00:01:40,159 local computer. This would be just like if they happen to have a new partition or a new hard disk, 14 00:01:40,159 --> 00:01:47,759 whatever it may be, on their local drive. However, it has been accessed, like I say again, via the 15 00:01:47,840 --> 00:01:55,520 network. And this really is the crux of what we are talking about here with respect to SAMBA. You 16 00:01:55,520 --> 00:02:00,240 may remember that we could implement particular authentication, meaning that we could share 17 00:02:00,240 --> 00:02:06,719 particular files with particular users or particular folders or printers, whatever it may be. But we 18 00:02:06,719 --> 00:02:13,200 were targeting particular individuals, certain people we wanted to grant access to certain files. 19 00:02:13,280 --> 00:02:18,159 In this case, though, what we're actually going to do is we're going to grant access to 20 00:02:18,159 --> 00:02:25,039 particular servers or to particular clients, i.e. we are no longer targeting individual user 21 00:02:25,039 --> 00:02:31,519 accounts. Instead, we are actually targeting particular machines. So really, if you want to 22 00:02:31,519 --> 00:02:38,239 share a file system with another server, the solution you should be looking at would be NFS. 23 00:02:38,239 --> 00:02:43,120 Now, with respect to NFS, we're going to have to talk about a few things. We're going to be looking 24 00:02:43,200 --> 00:02:50,159 at the actual server configuration. The NFS server would be the one who's actually sharing 25 00:02:50,159 --> 00:02:57,120 the file system. So that is where the file system is locally created. It's on the disk within that 26 00:02:57,120 --> 00:03:04,319 physical server. So if we just have the server here, and the machine which is using or rather 27 00:03:04,319 --> 00:03:10,080 accessing that file system over the network would be a client. So the client is receiving 28 00:03:10,080 --> 00:03:16,640 that file system or accessing it via NFS. So we're going to be looking at the server configuration 29 00:03:16,640 --> 00:03:22,560 within this skill, as well as the basic client configuration. And we'll also have to discuss 30 00:03:22,560 --> 00:03:27,520 how we can actually control permissions here. Because if you recall, with respect to Samba, 31 00:03:27,520 --> 00:03:32,720 we had particular styles of locking down security and access. We would have particular 32 00:03:32,720 --> 00:03:38,800 user names and passwords for particular users. But as we now know, NFS does not work on that 33 00:03:38,800 --> 00:03:46,080 user basis. It's going to be locking down things based on the server or the machine, if you will. 34 00:03:46,080 --> 00:03:51,840 Certain machines we want to grant access to, but perhaps maybe there are other machines that we 35 00:03:51,840 --> 00:03:58,400 want to not grant that access to. So this is something we're going to have to consider absolutely, 36 00:03:58,400 --> 00:04:04,800 and we'll get to that within this skill. But with respect to how NFS actually operates, 37 00:04:04,800 --> 00:04:10,080 we need to know a few basic components. The first thing we want to be aware of is that 38 00:04:10,080 --> 00:04:18,560 NFS is going to use something called RPC. Now all RPC is, it is a protocol that is going to 39 00:04:18,560 --> 00:04:27,040 facilitate some type of communication. Now, RPC actually stands for a remote procedure call. 40 00:04:27,040 --> 00:04:34,319 And this protocol really does shine with respect to client server architectures 41 00:04:34,319 --> 00:04:39,439 in a distributed fashion. So this really is a great fit for the type of solution that we want 42 00:04:39,439 --> 00:04:45,759 to actually implement here, being able to share out particular file systems across different devices 43 00:04:45,759 --> 00:04:52,879 within our network. Now, one thing to note about NFS with respect to the LPIC2 examination 44 00:04:52,879 --> 00:04:58,959 is that NFS does have two relevant versions that we want to be aware of. There is going to be a 45 00:04:58,959 --> 00:05:05,199 version three, which is what we will be looking at a little bit more closely. But we also have 46 00:05:05,199 --> 00:05:11,600 the newer version four, but the LPIC2 exam objectives really just request that we have 47 00:05:11,600 --> 00:05:18,159 an awareness of version four. So more of our time is going to be looking at how version three 48 00:05:18,160 --> 00:05:26,240 actually operates. Now, version three is going to leverage something called RPC Bind or something 49 00:05:26,240 --> 00:05:34,000 called Port Mapper. Now, whether you're using RPC Bind or Port Mapper, RPC Bind being the newer 50 00:05:34,000 --> 00:05:41,520 implementation. So really RPC Bind or Port Mapper is going to be in between the communication of 51 00:05:41,520 --> 00:05:47,520 the server sharing and the client, which is consuming RPC Bind or Port Mapper is going to 52 00:05:47,519 --> 00:05:52,799 handle that communication and the interaction between these two different components. Now, 53 00:05:52,799 --> 00:05:59,439 the reason why this is important is that because we have this intermediary with respect to version 54 00:05:59,439 --> 00:06:06,719 three, i.e. we have Port Mapper or RPC Bind in play, the reason why that is so important is because 55 00:06:06,719 --> 00:06:13,439 this is going to affect or at least can affect access to these particular shares. Because as 56 00:06:13,439 --> 00:06:19,680 we're going to see, you can actually control access to a particular server by specifying the 57 00:06:19,680 --> 00:06:26,480 devices or the devices within a certain network, which are allowed to access these network shares. 58 00:06:26,480 --> 00:06:32,639 And you can do this directly via NFS. And we'll get to see what that looks like in the next nugget. 59 00:06:32,639 --> 00:06:41,120 But we can also control access via TCP wrappers. And this is implemented at the level of either RPC 60 00:06:41,120 --> 00:06:48,079 Bind or Port Mapper. So the point is I'm trying to highlight here is that if we happen to have a 61 00:06:48,079 --> 00:06:54,800 particular clash, i.e. we have our server here with particular permissions, and we have our client 62 00:06:54,800 --> 00:07:01,199 here, which wants to consume these shares to be able to use, because we have this intermediary on 63 00:07:01,199 --> 00:07:08,959 the server, such as Port Mapper, if Port Mapper is implementing strict access controls that actually 64 00:07:09,039 --> 00:07:17,359 prevent the client from connecting, then even if you happen to have relaxed rules on the NFS server, 65 00:07:17,359 --> 00:07:24,240 the controls specified within Port Mapper can still override ultimately and prevent that access. 66 00:07:24,240 --> 00:07:30,079 So basically on your NFS configuration, you could pretty much say anyone can access this server, 67 00:07:30,079 --> 00:07:36,560 but via using TCP wrappers via Port Mapper, you may lock down that access. And in which case, 68 00:07:36,560 --> 00:07:43,360 even though NFS itself is configured to allow absolutely anyone to use this particular share, 69 00:07:43,360 --> 00:07:50,480 the client here can't actually get access due to the TCP wrapper configuration via Port Mapper or 70 00:07:50,480 --> 00:07:57,120 via RPC Bind. So this is something we want to be aware of with respect to version three and 71 00:07:57,120 --> 00:08:03,040 version four. When we're talking about version four, like I say, we don't need to worry about RPC Bind 72 00:08:03,120 --> 00:08:10,800 or Port Mapper. Instead, all of this stuff is ultimately handled natively within NFS 73 00:08:10,800 --> 00:08:17,520 version four. So that means within NFS version four, the security and the access permissions are 74 00:08:17,520 --> 00:08:24,879 handled natively. NFS does this all on its own. Now with respect as to how to specify who can 75 00:08:24,879 --> 00:08:30,960 actually access the NFS share, we're going to see how we can actually configure this. Now the 76 00:08:30,959 --> 00:08:35,679 general syntax is really quite simple. We're going to go into a configuration file, which we'll see 77 00:08:35,679 --> 00:08:42,399 in the very next nugget. We'll specify the share that we want to share out, i.e. the particular 78 00:08:42,399 --> 00:08:48,799 file system. Then we're going to specify who is actually allowed access to that particular share. 79 00:08:48,799 --> 00:08:55,840 And then within brackets, after we specify who is allowed access to the share, we're going to specify 80 00:08:55,840 --> 00:09:02,879 the permissions they actually have, i.e. what can this person who can access this share, what can 81 00:09:02,879 --> 00:09:08,160 they actually do on that share? Can they just read information on that share? Can they actually make 82 00:09:08,160 --> 00:09:14,080 changes? So on and so forth. So that really is the general outline for what we have to look at within 83 00:09:14,080 --> 00:09:20,000 this skill. The very first thing now, which I want to talk about is that NFS server configuration. 84 00:09:20,000 --> 00:09:23,759 And well, that's what we're going to be talking about in the very next nuggets. I hope this has 85 00:09:23,759 --> 00:09:27,039 been informative for you and I'd like to thank you for viewing.