SO you followed 2 different install guides? I've seen lots of problems when people use install guides other than the vendors guide for the version they are installing.
But, from the error, does the /tmp/elasticsearch-xxx.xxx/ directory exist?
No, the folder does not exist.
The first attempt follows the guide linked in the OP while the second follows the official guide from the website (https://www.elastic.co/guide/en/elasticsearch/reference/current/getting-started-install.html).
Both using a clean install of 18.04.2 LTS, and the second attempt on VirtualBox.
First log on the first post and second log on the second post.
I tried to install it on an old laptop and it worked at my first attempt, using the guide from the ES website.
I think that my desktop CPU is even older:
Memory: 9,3 GiB
Processor: AMD® Phenom(tm) ii x4 955 (2009)
OS type: 64-bit
Disk: 116,6 GB
user@guest:~/elasticsearch-6.8.1$ cd distribution/src/bin
user@guest:~/elasticsearch-6.8.1/distribution/src/bin$ ./elasticsearch
Error: Could not find or load main class org.elasticsearch.tools.java_version_checker.JavaVersionChecker
Caused by: java.lang.ClassNotFoundException: org.elasticsearch.tools.java_version_checker.JavaVersionChecker
I can install it but not run it.
I give up and maybe check it out later on when I have a new computer.
Sucks because Ubuntu/Mint is quite snappy on this machine.
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