Issue 10389#0: \996867 upstream sent too big header while reading response header from upstream

[tomass]

i got a website which is built using CMS Made Simple and one section of the admin panel(CMSMS) i.e. Content>Pages section is throwing bad gateway error, the rest section the admin panel is working fine. And earlier before the 500 error, whenever i tried to create a page through Content>Pages it just directed me to admin login page!!