June 29th, 2011, 02:55 AM
Active/passive broadband connections to maintain various IT services
plan to buy a firewall support active and passive internet connections, when active internet connection down, will failover to passive internet connection automatically, when active internet connection back on, will rollback to active internet connection automatically. Found a sonicwall should able to do this already.
public ip, default gateway and dns are different for active and passive internet connections, so when failover or rollback, they will change as well
IT services to maintain when active internet connection down are
- office internet access
- email service provided by exchange 2007
- internal/external web-based erp service provided by apache tomcat
office internet access
- achieve by add passive internet connection DNS to Windows DNS forwarder
email service provided by exchange 2007
- smtp achieve by additional MX record with passive internet connection's public IP and larger Preference Number (lower priority)
internal/external web-based erp service provided by apache tomcat
- By additional A record with passive internet connection's public IP for apache tomcat
Any idea what need to do to maintain Outlook Anywhere and Outlook Web Access? Just additional A record as well?
Thx a lot!
June 29th, 2011, 04:24 AM
You tried the Mail Server, DNS, Apache, and even Security and Cryptography forums without even noticing the Networking forum?
June 29th, 2011, 10:37 AM
Sorry, requinix, I have to disagree, this is definitely a DNS question.
Sorry c.itech for having this moved around so much. We're just trying to get you to the right audience.
June 29th, 2011, 11:11 AM
Your best bet would be something such as Simple Failover (http://www.simplefailover.com/). This system will allow you to enter multiple addresses for a host. The program queries the host every now and then and when it detects it as being down, it will rewrite the DNS records for the new IP address. And when the primary IP comes back up, it will swap the records back.
I have used this software but by no means am familiar with it's in's and out's though. So I don't have too much detail. But I know it worked as intended when I used it a while ago. You may want to search around for some failover dns software as I'm sure there is a lot on the internet somewhere.
There are drawbacks though to using failover DNS. You must keep a low ttl so there will be a significant amount of increased queries. There's also a lot of room for mistakes. And a mistake in DNS can be very bad if you have something cached and a large ttl on it.