1 00:00:00,000 --> 00:00:00,960 In this lesson, 2 00:00:00,960 --> 00:00:03,840 we're going to discuss RPM and YUM packages. 3 00:00:03,840 --> 00:00:06,120 RPM and YUM packages are important 4 00:00:06,120 --> 00:00:08,670 because they're used to conduct Linux package management 5 00:00:08,670 --> 00:00:12,510 inside of Red Hat-based distributions like CentOS. 6 00:00:12,510 --> 00:00:14,730 Now, they're going to be used to install, patch, 7 00:00:14,730 --> 00:00:18,210 and remove software packages on your Linux machine. 8 00:00:18,210 --> 00:00:19,770 Now, these are some of the most common tasks 9 00:00:19,770 --> 00:00:22,020 that you're going to do as a system administrator. 10 00:00:22,020 --> 00:00:24,090 And because of this, it's really important 11 00:00:24,090 --> 00:00:25,830 that you gain this essential skill 12 00:00:25,830 --> 00:00:28,110 to understand how to manage your packages. 13 00:00:28,110 --> 00:00:29,490 Different Linux distributions 14 00:00:29,490 --> 00:00:31,710 will use different package management tools, 15 00:00:31,710 --> 00:00:33,900 but if you're using Red Hat-based distributions, 16 00:00:33,900 --> 00:00:38,250 like CentOS, you can use RPM or the Red Hat Package Manager 17 00:00:38,250 --> 00:00:40,410 or you can use YUM or DNF, 18 00:00:40,410 --> 00:00:44,610 which is the Yellowdog Updater, Modified or Dandified YUM. 19 00:00:44,610 --> 00:00:46,680 Now, the RPM command is going to be used 20 00:00:46,680 --> 00:00:50,640 to manage RPM packages on Red Hat-derived distributions. 21 00:00:50,640 --> 00:00:53,790 It has options including -i and the package name 22 00:00:53,790 --> 00:00:56,730 which you use to install the specified software package. 23 00:00:56,730 --> 00:00:59,029 If you use -e and the package name, 24 00:00:59,029 --> 00:01:02,430 this is going to be used to erase or uninstall the package. 25 00:01:02,430 --> 00:01:05,010 v is going to be used to enable verbose mode 26 00:01:05,010 --> 00:01:07,140 which gives you more details and error messages 27 00:01:07,140 --> 00:01:08,253 if things go wrong. 28 00:01:09,090 --> 00:01:11,160 h is going to be used to print hash marks 29 00:01:11,160 --> 00:01:12,450 to indicate a progress bar 30 00:01:12,450 --> 00:01:14,340 as you're installing the software. 31 00:01:14,340 --> 00:01:17,400 And -V and the package name is going to be used 32 00:01:17,400 --> 00:01:19,890 to verify the software components of the package 33 00:01:19,890 --> 00:01:21,450 to ensure they exist. 34 00:01:21,450 --> 00:01:22,860 To run the RPM command, 35 00:01:22,860 --> 00:01:26,700 simply type in rpm, the options, and the package name. 36 00:01:26,700 --> 00:01:28,110 Now, one of the most powerful features 37 00:01:28,110 --> 00:01:29,880 of the RPM Package Manager 38 00:01:29,880 --> 00:01:31,770 is the ability for it to maintain a database 39 00:01:31,770 --> 00:01:33,510 of software information. 40 00:01:33,510 --> 00:01:36,000 This database will enable you as an administrator 41 00:01:36,000 --> 00:01:38,250 to discover the package version information, 42 00:01:38,250 --> 00:01:40,380 to have a list of all the installed software, 43 00:01:40,380 --> 00:01:43,380 to discover dependency information, and much more. 44 00:01:43,380 --> 00:01:45,180 If you want to be able to query this database 45 00:01:45,180 --> 00:01:46,620 and get information about it, 46 00:01:46,620 --> 00:01:50,220 you can do that by typing in rpm -qa 47 00:01:50,220 --> 00:01:52,380 to list all the installed software. 48 00:01:52,380 --> 00:01:55,890 If you type in rpm -qi and the package name, 49 00:01:55,890 --> 00:01:59,070 this'll list information about a single particular package. 50 00:01:59,070 --> 00:02:01,837 And if you use rpm -qc and the package name, 51 00:02:01,837 --> 00:02:04,620 this will list out all the configuration files 52 00:02:04,620 --> 00:02:06,450 for a particular package. 53 00:02:06,450 --> 00:02:07,283 Now, as I said, 54 00:02:07,283 --> 00:02:11,190 RPM can also be used to validate and verify your software. 55 00:02:11,190 --> 00:02:12,870 This verification will check to see 56 00:02:12,870 --> 00:02:14,670 if the installed software components 57 00:02:14,670 --> 00:02:17,310 are matching what the RPM package specifies 58 00:02:17,310 --> 00:02:18,960 that should have been installed. 59 00:02:18,960 --> 00:02:20,580 The verify option is going to be used 60 00:02:20,580 --> 00:02:22,410 to troubleshoot installed software 61 00:02:22,410 --> 00:02:24,840 and ensure that the entire software package is installed, 62 00:02:24,840 --> 00:02:27,120 and valid, and working properly. 63 00:02:27,120 --> 00:02:27,960 To do this, 64 00:02:27,960 --> 00:02:32,430 you're going to use rpm -V and the package name. 65 00:02:32,430 --> 00:02:34,050 Now part of the software lifecycle 66 00:02:34,050 --> 00:02:36,000 is also to keep your software current 67 00:02:36,000 --> 00:02:38,130 with the latest versions and updates. 68 00:02:38,130 --> 00:02:41,730 RPM offers two primary ways for you to accomplish this goal. 69 00:02:41,730 --> 00:02:44,790 The first is to use the -U option. 70 00:02:44,790 --> 00:02:46,980 This will be used to upgrade the installed package 71 00:02:46,980 --> 00:02:50,010 and then install the package if it's not already installed. 72 00:02:50,010 --> 00:02:53,130 The second method is use the -F option. 73 00:02:53,130 --> 00:02:55,500 This is known as the freshen option. 74 00:02:55,500 --> 00:02:57,630 Now, when you freshen the installed package, 75 00:02:57,630 --> 00:03:00,180 this is going to update the package if it's installed. 76 00:03:00,180 --> 00:03:02,220 But, if it's not already installed, 77 00:03:02,220 --> 00:03:03,750 it's not going to do anything 78 00:03:03,750 --> 00:03:06,420 because you're just freshening an existing install. 79 00:03:06,420 --> 00:03:08,880 So remember, if you use -U, 80 00:03:08,880 --> 00:03:11,580 you will install the package if it doesn't already exist 81 00:03:11,580 --> 00:03:14,100 or you'll upgrade the package if it does. 82 00:03:14,100 --> 00:03:18,840 With -F, you will only upgrade the package if it exists. 83 00:03:18,840 --> 00:03:20,400 The yum command is another way 84 00:03:20,400 --> 00:03:22,260 that you can use package management. 85 00:03:22,260 --> 00:03:25,200 The yum command improves on the functionality of RPM 86 00:03:25,200 --> 00:03:28,080 while still using those RPM packages themself 87 00:03:28,080 --> 00:03:30,390 and maintaining an RPM database. 88 00:03:30,390 --> 00:03:32,070 This provides a more straightforward method 89 00:03:32,070 --> 00:03:33,570 for you to manage your packages 90 00:03:33,570 --> 00:03:36,540 and works as an upgraded version of RPM. 91 00:03:36,540 --> 00:03:39,330 One of the biggest benefits of using yum is its ability 92 00:03:39,330 --> 00:03:41,970 to automatically handle software dependencies. 93 00:03:41,970 --> 00:03:43,860 This means that administrators can tell yum 94 00:03:43,860 --> 00:03:45,540 to install a particular package 95 00:03:45,540 --> 00:03:46,950 along with automatically installing 96 00:03:46,950 --> 00:03:48,540 all the additional packages 97 00:03:48,540 --> 00:03:50,670 that that thing depends upon. 98 00:03:50,670 --> 00:03:54,180 An additional yum benefit is also the use of repositories. 99 00:03:54,180 --> 00:03:56,100 Now repositories enable administrators 100 00:03:56,100 --> 00:03:59,460 to more easily maintain version control over the software. 101 00:03:59,460 --> 00:04:02,160 The yum command comes with lots of different sub commands 102 00:04:02,160 --> 00:04:04,260 that you can use to manage your packages. 103 00:04:04,260 --> 00:04:07,830 For example, if you type yum install and the package name, 104 00:04:07,830 --> 00:04:08,970 this will install the package 105 00:04:08,970 --> 00:04:11,160 from any configured repository. 106 00:04:11,160 --> 00:04:13,980 If you use yum local install package name, 107 00:04:13,980 --> 00:04:16,860 this will install the package from the local repository. 108 00:04:16,860 --> 00:04:19,230 If you use yum remove package name, 109 00:04:19,230 --> 00:04:21,240 this will uninstall your package. 110 00:04:21,240 --> 00:04:23,700 If you use yum update package name, 111 00:04:23,700 --> 00:04:25,680 this will update the package. 112 00:04:25,680 --> 00:04:27,660 If you want to update all of your software, 113 00:04:27,660 --> 00:04:30,750 you can do this by typing yum update and hitting enter 114 00:04:30,750 --> 00:04:33,270 and this will update all of your installed packages. 115 00:04:33,270 --> 00:04:34,650 Now note, if you do this, 116 00:04:34,650 --> 00:04:37,140 it is going to download all the updates and install them 117 00:04:37,140 --> 00:04:39,600 so this can actually take quite a bit of time. 118 00:04:39,600 --> 00:04:42,420 If you type in yum info and the package name, 119 00:04:42,420 --> 00:04:43,620 this will provide information 120 00:04:43,620 --> 00:04:45,660 about the package that's installed. 121 00:04:45,660 --> 00:04:48,480 And if you use yum provides file name, 122 00:04:48,480 --> 00:04:51,270 this will provide a report of what the package provides 123 00:04:51,270 --> 00:04:53,580 for specified files and libraries. 124 00:04:53,580 --> 00:04:55,680 Essentially listing out everything that was installed 125 00:04:55,680 --> 00:04:57,540 for that particular package. 126 00:04:57,540 --> 00:04:59,970 If you want to run the yum command in general, 127 00:04:59,970 --> 00:05:02,310 you're simply going to type in yum, the options, 128 00:05:02,310 --> 00:05:05,040 the sub command and the package name. 129 00:05:05,040 --> 00:05:06,450 Now, another thing you might use 130 00:05:06,450 --> 00:05:09,540 inside of your yum is the -y option. 131 00:05:09,540 --> 00:05:12,600 The -y option is going to automatically answer yes 132 00:05:12,600 --> 00:05:14,940 to installing additional software dependencies 133 00:05:14,940 --> 00:05:16,800 when you're trying to install a package. 134 00:05:16,800 --> 00:05:18,030 If you don't do this, 135 00:05:18,030 --> 00:05:20,460 yum is actually going to prompt you to answer yes or no 136 00:05:20,460 --> 00:05:23,340 to each and every dependency that it wants to install 137 00:05:23,340 --> 00:05:25,170 based on the software you asked. 138 00:05:25,170 --> 00:05:27,510 Now, if you don't understand the concept of dependencies, 139 00:05:27,510 --> 00:05:29,070 think about it this way. 140 00:05:29,070 --> 00:05:31,020 If I wanted to create a new program, 141 00:05:31,020 --> 00:05:33,750 there's lots of existing code that already exists out there. 142 00:05:33,750 --> 00:05:36,240 So would I want to rewrite everything from scratch? 143 00:05:36,240 --> 00:05:37,590 Well, probably not. 144 00:05:37,590 --> 00:05:40,950 So instead, I can link to other libraries that exist. 145 00:05:40,950 --> 00:05:43,890 For example, if you're used to using a Windows machine, 146 00:05:43,890 --> 00:05:47,520 every single Windows software has the same basic features 147 00:05:47,520 --> 00:05:50,070 where you can open a file or save a file. 148 00:05:50,070 --> 00:05:50,910 It'd be kind of dumb 149 00:05:50,910 --> 00:05:52,860 if everyone had to code that themselves. 150 00:05:52,860 --> 00:05:55,110 So instead, there's a library you can call 151 00:05:55,110 --> 00:05:58,080 that's called the file input output system, right? 152 00:05:58,080 --> 00:06:00,720 And that way you can choose to just reference 153 00:06:00,720 --> 00:06:03,690 the open dialogue box or the save dialogue box 154 00:06:03,690 --> 00:06:04,890 using a single line of code 155 00:06:04,890 --> 00:06:07,320 and everything else will be run by that library. 156 00:06:07,320 --> 00:06:09,180 That now becomes a dependency. 157 00:06:09,180 --> 00:06:12,060 And so when I go and give you my source code or my package 158 00:06:12,060 --> 00:06:13,410 and you try to install it, 159 00:06:13,410 --> 00:06:16,590 it now says in addition to installing Jason's new program, 160 00:06:16,590 --> 00:06:19,680 I also need to install the file input output library 161 00:06:19,680 --> 00:06:22,290 that was a dependency of Jason's program. 162 00:06:22,290 --> 00:06:23,123 If you have to figure out 163 00:06:23,123 --> 00:06:24,450 all those dependencies on your own, 164 00:06:24,450 --> 00:06:26,280 it can be a nightmare, 165 00:06:26,280 --> 00:06:28,770 but by using packages, you don't have to do that 166 00:06:28,770 --> 00:06:31,260 because yum is going to find all those dependencies 167 00:06:31,260 --> 00:06:32,400 and install them for you, 168 00:06:32,400 --> 00:06:34,530 as long as you tell it to. 169 00:06:34,530 --> 00:06:36,810 Finally, when it comes to RPM packages, 170 00:06:36,810 --> 00:06:40,110 we can also use DNF as our package manager. 171 00:06:40,110 --> 00:06:41,850 To install a package using DNF, 172 00:06:41,850 --> 00:06:45,090 simply type in dnf install and the package name. 173 00:06:45,090 --> 00:06:46,860 To uninstall a package using DNF, 174 00:06:46,860 --> 00:06:50,040 simply type in dnf remove and the package name. 175 00:06:50,040 --> 00:06:52,530 In general, most of the sub commands used by YUM 176 00:06:52,530 --> 00:06:54,750 are going to also work in DNF 177 00:06:54,750 --> 00:06:56,250 and if you want to learn more about DNF, 178 00:06:56,250 --> 00:06:57,480 you can check the man pages 179 00:06:57,480 --> 00:07:00,060 by typing man dnf and pressing enter 180 00:07:00,060 --> 00:07:01,710 in your command line environment.