I know of 2 instances in Southeast Asia where chains were claimed to have been used in the manner you describe. Unfortunately, I don’t have a lot of details.

The more recent instance is during the third Anglo-Burmese War (1885). Historian Michael Charney mentions that Tarsillo Barberis, an Italian captain fighting on the Burmese side, later wrote in his memoirs that the Burmese ‘attempted to use chains in order to prevent British ships from ascending the Irrawaddy beyond Minhla’. I am unfortunately unable to find the primary source mentioned so cannot provide the exact quote or context.

There is another, much older, claim of a chain being used by Srivijaya in what is now Sumatra. This comes from the 诸蕃志 (Zhu Fan Zhi, A Description of Barbarian Nations). This was written around 1225 by Zhao Rugua, a customs officer in Quanzhou:

其国在海中扼诸番舟车往来之咽喉，古用铁索为限以备他盗操纵，若有机商舶至则纵之。比年宁谧，撤而不用，堆积水次。土人敬之如佛，舶至则祠焉沃，以油则光焰如新。鳄鱼不敢踰为患。

The translation by Friedrich Hirth and William Woodville Rockhill:

This country, lying in the ocean and controlling the straits through which the foreigners' sea and land traffic in either direction must pass, in olden times used an iron chain as a barrier to keep the pirates of other countries in check. It could be kept up or lowered by a cunning device. If a merchant ship arrived it was lowered. After a number of years of peace, during which there has been no use for it, it has been removed and (now) lies coiled up on the shore. The natives reverence it like a Buddha, and vessels coming there sacrifice to it. When rubbed with oil it shines like new. Crocodiles do not dare pass over it to do mischief.

As far as we know, Zhao never went to Srivijaya to look at this chain himself. Instead, he received this information second hand, probably from Srivijayan merchants operating in Quanzhou. Thus, we don’t know how true this statement is. Srivijaya left behind very little of its own, so at this time we are unable to definitively say whether the chain actually existed, how it was operated, how long it was etc.

Charney, M. (2004). Southeast Asian Warfare, 1300-1900. Leiden, The Netherlands: Brill.

Chao, J., Hirth, F., & Rockhill, W. W. (1966). Chau Ju-kua: His work on the Chinese and Arab trade in the twelfth and thirteenth centuries, entitled Chu-fan-chi. Translated from the Chinese and annotated by Friedrich Hirth and W.W. Rockhill. Amsterdam: Oriental Press.