Actually, I have just found out it was due to the i18n setting of the node and site. The language of the node was set to be ja (Japanese), correctly. Probably because of that,
does not work (HTTP 404), but
does display the node imported.
Similarly, the Content manager does not display the node in the default-language mode (English)
/admin/content, however it does display the newly imported node in Japanese
/ja/admin/content. I should note I allow all the URL (Path prefix), Session, User, Browser in the language configuration (
/admin/config/regional/language/configure) in my environment.
My browser's HTTP request, when I test, is
So, I expected when I opened
it would open the node in Japanese, following the browser's request, as opposed to 404, but it does not, apparently.
Hmm, I guess it is likely my understanding of the i18n handling in Drupal is not sufficient. Anyway, I think this can be solved with the redirection module in Drupal, after investigating and finding out how to set it up during migration. I didn't want the default URI to be something like
node/21, but if it is
ja/info/legacy.html, I am fine with it, as long as the redirection works.
I have figured out why. In my i18n setting of Drupal, URI-path-prefix is checked and is given the highest priority, where English is default with its language-code for path-prefix being undefined. Hence,
is the English version of the content, which does not exist. When I define the language-code of English (en) for path-prefix, then the access to the URI brings up the Japanese version, if my browser's preferred language is Japanese (and the i18n of the site is configured to accept the browser's preferred language at the lowest priority), because the URI is not any more specific for the English version.
Another note is the redirection module works only when redirecting to a node URI [or path without the language-code prefix (added on 2014-10-11)]. The redirection to, for example,
does not work well, as it can bring up the path of
in some cases.
The whole point (and much more) is covered and summarised in the document published at drupal.org: https://www.drupal.org/node/2354755