I'm upgrading from CentOS6 to CentOS 7. I run 2 weather stations on C6 and have one of them attached to ttyS0 which is on the motherboard, and the other to ttyS2 which in on an add-on PCI serial card. I'm migrating the weather stations another host running C7 which has a similar hardware configuration. When I connect the weather station to ttyS0 everything works fine, but when I try to use ttyS1 or ttyS2 nothing happens. The OS identifies all 3 ports, and I've already tried several different serial cards several of the slots on the motherboard all have yielded the same result. I've even gone so far as to try to get this to work on another computer running C7 with the same result, success on ttyS0, but nothing nothing when I try ttyS1 or ttyS2. I'm thinking that this might be a driver issue, but having used several different cards I'm just not sure. Any assistance would be greatly appreciated. Pete -- Unencumbered by the thought process. -- Click and Clack the Tappet brothers -- This message has been scanned for viruses and dangerous content by MailScanner, and is believed to be clean.