Wairangi Wharf Reserve is listed as a campground in Arch Hill, Auckland City, with a Google rating of 4.6.
A good campground keeps the basics in order: a safe, level place to stay, clear rules about fires, dogs, noise and how long you can stay, and toilets and rubbish arrangements that are kept in good order. Before you go, check whether it is a formal camp or a free reserve, since free sites often have limits such as self-contained vehicles only and no facilities. Look up the latest rules with the local council or the camp's own page, because they change. Regulars arrive early in summer and on long weekends, take all their rubbish away and leave the site as they found it, which keeps these places open to everyone. Pack water, sun protection and a charged phone.
For anyone planning a stay around Auckland, Wairangi Wharf Reserve is worth checking for current rules before you set out.