Sleep Training

Any opinions on Ferber or other methods of sleep training?

My 7 month old son used to sleep through the night then was waking every 3 hours. Now we're down to one or two wakings but he seems to be having some separation anxiety and it can take over an hour to get him back to sleep. He cries anytime my husband or I put him down and needs comforting. His naps are becoming difficult as well and are getting shorter and shorter.

I think he needs more sleep and it's hard on us emotionally and physically with his waking and being so upset.

I'm only sure if it's a bad idea to sleep train during this sensitive time or if we continue on this way will we make bad habits? Teething also seems to be an ongoing issue.

TIA!