The serial card problem is a bit mystifying. It didn't happen in CHATS, and we had about the same or more load on the data system.
Systems with the Emerald 8P cards seem to be the ones that are failing. I don't believe we had those at CHATS. So I'm removing them from our systems.
upwind: had 1 8P card and 1 8M. It was only using 7 ports on the 8P and none on the 8M, so I removed the 8P and cabled the 8M as the first and only card. There is still an available port for the 15th pressure system.
downwind2: removed 8P W274177, installed 8M W240036, which is a spare card. This board has a dead port #1 (numbered from 0) which is /dev/ttyS6 when it is installed as the first card. To minimize the cabling changes. I installed W240036 as the second card, and so W249924 is now the first card. This means that port /dev/ttyS14 is now dead, and the last sonic was switched to /dev/ttyS15.
Currently the profile tower has the only remaining 8P card (and it has been working quite well since we improved the voltage level).