Start script is not executed on system with noexec flag for /tmp

[tyzhnenko]

Some systems has noexec flag for /tmp folder. In this case one-context can't execute user script while booting. Look error log bellow

Possible solution is give to users ability set TMP_BASE variable and use it instead of hadrcode like sthi TMP_DIR=$(mktemp -d "/tmp/one-context.XXXXXX")

TMP_BASE=$(TMP_BASE:-/tmp}
TMP_DIR=$(mktemp -d "$TMP_BASE/one-context.XXXXXX")

journalctl -u one-context | grep start-script

start-script output: /etc/one-context.d/net-97-start-script: line 21: /tmp/one-context.yKZcbb/one-start-script: Permission denied

[tyzhnenko]

@vholer I've push a PR. Let's use EXEC_TMP_BASE for variable. I guess that can help users not to be confused and they will understand that variable reletes only to user script execution part.

[vholer]

Hi. There is already issue OpenNebula/one-apps#34 to make most things configurable, it should by done in a single task at once with consistent naming in wide context. So, I'm not going to merge the PR until at least an analysis of OpenNebula/one-apps#34 is done. Thank you for understanding.