.-CHANCON--=--COND-------. >>-+------------------------+---------------------------------->< | .-COND---. | '-CHANCON--=--+--------+-' '-UNCOND-'
| statements: | GROUP, LINE, PU |
| dependencies: | LNCTL=NCP |
Determines
whether VTAM® sends a conditional
or an unconditional channel Contact request to the NCP when the host
is to activate an NCP over a channel.
- CHANCON=COND
- VTAM allows the NCP to reject the host’s Contact request if the host’s subarea number is already in use by another host (attached to another of the NCP’s channels). This results when duplicate subareas are assigned to more than one host (attached to more than one channel interface). For instance, two hosts might have inadvertently been assigned the same number, or they might have been assigned duplicate numbers to allow mutual backup capabilities.
- CHANCON=UNCOND
- VTAM sets an indicator in the channel Contact request that forces the NCP to accept the Contact request regardless of whether a host with that subarea number is currently channel-attached to that NCP. If another host using the same subarea number is channel-attached to the NCP, the NCP breaks contact with the host on the other channel.