I have Televantage server with Toshiba DKT2010, DKT2020 digital phones and voice T1(23 trunks). We have failover voice T1 other than the primary voice T1. So, the phone line is fine.
However, I'm looking for any cheap, simple PBX which can be kept as a backup to replace televantage server 7. Do you know any recommendation? We operate more phones, but for this backup pbx, if it can handle 10 phones, 1 incomming call queue, takes voice T1 should be fine until we fully recover the main televantage pbx.
I tried many different voip, sip service, but it doesn't seem working well. So voip,sip is not my options. As long as I have voice T1 line, I need to utilize for the situation when Televantage fails.