{"id":578,"date":"2019-12-16T12:00:00","date_gmt":"2019-12-16T20:00:00","guid":{"rendered":"http:\/\/letsbuildroboticswithshadow8472.com\/?p=578"},"modified":"2019-12-02T15:22:45","modified_gmt":"2019-12-02T23:22:45","slug":"minecraft-server-week-5-wall-of-java-unsupported-management-version","status":"publish","type":"post","link":"https:\/\/letsbuildroboticswithshadow8472.com\/index.php\/2019\/12\/16\/minecraft-server-week-5-wall-of-java-unsupported-management-version\/","title":{"rendered":"Minecraft Server, Week 5: Wall of Java (Unsupported Management version)"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\">Good Morning from My Robotics Lab! This is Shadow_8472, and today, I am continuing work on this server project I&#8217;m getting a little tired of. Let&#8217;s get started!<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Timeline: This week was Thanksgiving, and I didn&#8217;t apply myself all day every day until Sabbath like I have the past two weeks. I&#8217;m also writing after the fact again.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Last week, I said I would drop the nuke. Well, I did. And the refugees I stored in my little silo gave me a world of trouble. All that trouble last week to preserve what I had, and something, somewhere was unaccounted for, and my little backup and restore scripts all for nothing but an exercise in shell scripting. <\/p>\n\n\n\n<p class=\"wp-block-paragraph\">While I eventually resorted to a clean install, I learned a few lessons. First, tce-load does not like being run with sudo. I should have remembered this, and come up with some creative solution to install nano and anything else I want to download automatically, but I abandoned that venture before perusing it. Second, something with the login data didn&#8217;t copy over correctly. Again, I cut this off before figuring out what exactly was going on. One thing I did keep was the hidden .ssh file for my user account.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Speaking of user accounts, I have noticed that project distros tend to give you a two character login, probably so you can get in easily when you have ssh set up with proper keys. BlinkiePie has a default &#8220;pi&#8221; account as a nod to it being a Raspberry Pi, while Micro Core&#8217;s default user name is &#8220;tc&#8221; as a nod to the flagship version of the distro, Tiny Core. While doing my clean install, I enshrined my favorite boot codes in the as part of the installation script, and came out with no trace of the tc username in with the encrypted passwords.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">With only a couple more obstacles, I loaded OpenJDK 8 on as that is the latest version available for &#8220;drag and drop&#8221; style installation unless I want to try making a .tcz file myself. I made a folder to test run the server .jar file and ran into an exception: &#8220;Unsupported Management Version.&#8221;<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Those three words defined the rest of my week in relation to this project.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Online searches bring up several near misses, but only a single page even contained the error in its entirety. Sometimes it even shows up twice, and it still doesn&#8217;t have any answers.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Several people tried to help me across a few Discord servers. One of my earlier help sessions involved trying to execute a HelloWorld! program. It failed, but only because I actually had do this little thing called &#8220;compilation.&#8221; A copy was scp&#8217;ed (Secure cp (copy), a part of SSH) off to Blinkie for compilation, tested, and ran fine when it came back and I wasn&#8217;t just trying to execute the source again.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">As a test, I tried copying a known good .jar file over from the intermediary server running on my father&#8217;s computer. I mounted the hard disk in the same case tried copying a .jar from a known good Spigot 1.13 server. Both gave slightly different versions of Unsupported Management version. The trace didn&#8217;t even lead to the same place!<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Taking a closer look at version numbers, I found that I was dealing with a seemingly slightly older build of Java than most of my other computers. If so, it might explain why things aren&#8217;t working, as Java supposedly only runs on the same or later version as it was compiled for. Besides, I may want to run a plugin or two some time, and it would be easiest if all versions on the server are running off a single version.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"> Blinkie seems to have the oldest build of Java 8, so I went over there and started setting up Build Tools, a script used in the distribution of Minecraft Spigot. As with anything that tends to spew files everywhere, I contained it in a box (directory). I ran Build Tools, and got a message about low RAM. It needs more than a 32 bit OS can address, and Raspian is a 32 bit distro intended for a 64 bit machine.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Even though Micro Core doesn&#8217;t even seem to have a Java compiler available in its repository, I tried running Build Tools straight on Micro Core. I didn&#8217;t expect it to work, and it didn&#8217;t. At least it provided me with a third Unsupported Management version example to study. I was honestly expecting it to fail due to lack of a compiler.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">From here on out, all I&#8217;ve done is research. I&#8217;ve poked this problem for days, I don&#8217;t know how to fix this yet. The first, and most obvious way would be to try Oracle JDK again, but I want to back everything up first, possibly by booting to Ubuntu, mounting Micro Core&#8217;s SSD, and using tar on the contents.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Another possibility is just scrapping everything and going with MineOS. It has all the features I&#8217;ll want, all packaged up nice and tidy. Backups, updates, premade start\/stop scripts for (multiple?) servers. It even has security considerations I haven&#8217;t even begun making plans for yet. Anyone can use it with minimal effort. It&#8217;s perfect &#8212; except that it would feel like a cop out. <\/p>\n\n\n\n<p class=\"wp-block-paragraph\">One of the reasons I&#8217;m doing this project is to learn whatever I need to function as an effective power user in Linux. I&#8217;ve learned so much on this one project, and I don&#8217;t want to take the easy way out this time. Even when looking at Build Tools again, I understand so much more than when <\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The other path I think I can develop is making a new .tcz file for a different version of OpenJDK. Since I don&#8217;t want to spend forever trying to do it on my own, I am going to try making an account on the Tiny Core forums. The development team reportedly patrols it, so if there&#8217;s any place I&#8217;m going to get help, that is it. It isn&#8217;t secure, so I&#8217;ll be using my password manager to generate a whopper for it.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Ultimately, this is a very niche problem. Normally, I like split the different parts when I have most of the plot threads tied off with progress made on the central thread. This post feels more frayed, but it&#8217;s a full week&#8217;s events. Happy Thanksgiving!<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Final Question: Every kind of computer interface has its own set of required basic actions we take for granted after a while. What kind of basic, but not too basic features do you take for granted in your interface of choice?<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Good Morning from My Robotics Lab! This is Shadow_8472, and today, I am continuing work on this server project I&#8217;m getting a little tired of. Let&#8217;s get started! Timeline: This week was Thanksgiving, and I didn&#8217;t apply myself all day every day until Sabbath like I have the past two weeks. I&#8217;m also writing after &hellip; <\/p>\n<p class=\"link-more\"><a href=\"https:\/\/letsbuildroboticswithshadow8472.com\/index.php\/2019\/12\/16\/minecraft-server-week-5-wall-of-java-unsupported-management-version\/\" class=\"more-link\">Continue reading<span class=\"screen-reader-text\"> &#8220;Minecraft Server, Week 5: Wall of Java (Unsupported Management version)&#8221;<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_bbp_topic_count":0,"_bbp_reply_count":0,"_bbp_total_topic_count":0,"_bbp_total_reply_count":0,"_bbp_voice_count":0,"_bbp_anonymous_reply_count":0,"_bbp_forum_subforum_count":0,"footnotes":""},"categories":[2,10],"tags":[],"class_list":["post-578","post","type-post","status-publish","format-standard","hentry","category-linux","category-minecraft"],"_links":{"self":[{"href":"https:\/\/letsbuildroboticswithshadow8472.com\/index.php\/wp-json\/wp\/v2\/posts\/578","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/letsbuildroboticswithshadow8472.com\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/letsbuildroboticswithshadow8472.com\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/letsbuildroboticswithshadow8472.com\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/letsbuildroboticswithshadow8472.com\/index.php\/wp-json\/wp\/v2\/comments?post=578"}],"version-history":[{"count":2,"href":"https:\/\/letsbuildroboticswithshadow8472.com\/index.php\/wp-json\/wp\/v2\/posts\/578\/revisions"}],"predecessor-version":[{"id":580,"href":"https:\/\/letsbuildroboticswithshadow8472.com\/index.php\/wp-json\/wp\/v2\/posts\/578\/revisions\/580"}],"wp:attachment":[{"href":"https:\/\/letsbuildroboticswithshadow8472.com\/index.php\/wp-json\/wp\/v2\/media?parent=578"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/letsbuildroboticswithshadow8472.com\/index.php\/wp-json\/wp\/v2\/categories?post=578"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/letsbuildroboticswithshadow8472.com\/index.php\/wp-json\/wp\/v2\/tags?post=578"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}