1 00:00:00,000 --> 00:00:10,280 In this video, we'll talk about some tools that allow you to monitor what is going on 2 00:00:10,280 --> 00:00:11,280 in your file system. 3 00:00:11,280 --> 00:00:15,480 We're talking about technical tools that are giving deep insight in the workings of your 4 00:00:15,480 --> 00:00:16,480 file system. 5 00:00:16,480 --> 00:00:19,799 Now, the tools are file system specific. 6 00:00:19,799 --> 00:00:26,160 On EXE4 file systems, Tune2FS will show and optimize your EXE file systems. 7 00:00:26,160 --> 00:00:30,600 There is DumpE2FS, which will dump EXE file system metadata. 8 00:00:30,600 --> 00:00:34,759 And XFS Admin is what you can use to monitor XFS properties. 9 00:00:34,759 --> 00:00:38,160 Let me show you. 10 00:00:38,160 --> 00:00:42,520 For this demo, I'm going to connect to my Ubuntu server for the simple reason that Ubuntu 11 00:00:42,520 --> 00:00:48,840 comes with EXE and CentOS, as well as Red Hat, are coming with XFS by default. 12 00:00:48,840 --> 00:00:55,279 So let me open a root shell, because really for these commands, we do need superuser privileges. 13 00:00:55,279 --> 00:00:57,880 And LSBLK is showing me what? 14 00:00:57,880 --> 00:01:02,160 Showing me my root logical volume right here. 15 00:01:02,160 --> 00:01:03,560 And I have an SCA2. 16 00:01:03,560 --> 00:01:08,879 Let's investigate SCA2 using Tune2FS. 17 00:01:08,879 --> 00:01:12,320 Minus L on dev SCA2. 18 00:01:12,320 --> 00:01:13,320 And what do we see? 19 00:01:13,320 --> 00:01:16,080 We see technical information about the file system. 20 00:01:16,080 --> 00:01:20,879 Now, this is not the information that you will be using on a daily basis. 21 00:01:20,879 --> 00:01:26,639 But sometimes it can be useful to check out file system features, for instance. 22 00:01:26,639 --> 00:01:29,879 There is this feature for the extended attributes. 23 00:01:29,879 --> 00:01:34,440 And these extended attributes are required to store additional information. 24 00:01:34,440 --> 00:01:38,040 Or what do you think of the default mount options? 25 00:01:38,040 --> 00:01:40,040 User XATR or ACL? 26 00:01:40,040 --> 00:01:44,360 Let's imagine that you are trying to set an attribute using chatter, or you are trying 27 00:01:44,360 --> 00:01:49,279 to use setFACL to set file system access control lists, and it doesn't work. 28 00:01:49,279 --> 00:01:54,040 Well, that is a moment where you want to dive into the file system organization to 29 00:01:54,040 --> 00:01:56,519 check if there is ACL support. 30 00:01:56,519 --> 00:01:57,519 And here you can see it. 31 00:01:57,519 --> 00:02:01,199 For the rest of it, you can see more technical metadata. 32 00:02:01,199 --> 00:02:06,800 An interesting one about EXT is that EXT has an inode count. 33 00:02:06,800 --> 00:02:12,320 So there is 114,688 inodes. 34 00:02:12,320 --> 00:02:16,919 Now one feature of EXT is that inodes are static. 35 00:02:16,919 --> 00:02:20,039 They are created when you create your file system. 36 00:02:20,039 --> 00:02:22,679 And that means that you can run out of inodes. 37 00:02:22,679 --> 00:02:28,000 Now fortunately on this system, we still have a lot of inodes available. 38 00:02:28,000 --> 00:02:29,839 So we are far from this system. 39 00:02:29,839 --> 00:02:35,759 But if ever you get an inode unavailable message, well, requesting information about your file 40 00:02:35,759 --> 00:02:38,639 system might be convenient. 41 00:02:38,639 --> 00:02:42,759 You can get even more data by using the dump utility. 42 00:02:42,759 --> 00:02:50,479 Our dump E2FS on dev SCA2, for instance, is giving detailed information about block 43 00:02:50,479 --> 00:02:51,479 groups. 44 00:02:51,479 --> 00:02:55,639 This is really going deep, and many administrators never get there. 45 00:02:55,639 --> 00:03:00,080 As you can see in the beginning, we have the same output as tune2fs-l. 46 00:03:00,080 --> 00:03:02,199 But then we get into the block groups. 47 00:03:02,199 --> 00:03:08,520 EXT file systems are organized in block groups for more logical storage of your files. 48 00:03:08,520 --> 00:03:12,199 And if you want details about these block groups, well, you can see it right here.