What do i need to have redundant internet connection for servers?



  • As the topic says, I would like to get a connection from two different ISPs to have a redundant and hopefully a faster connection to the internet. What do I need from my ISPs? I want to use the same IP-adresses from both ISPs.

    I have heard about BGP but it seams very complex for my skill-level.

    Is it possible to have the ISPs give out a sort of "bonded" setup. So i can just set the wan-interface to be bonded with a connection from each ISP and use normal balance-rr?

    Could i mix this with CARP and PFSync? BGP sounds scary and I don't think i'm up to the challenge sadly.



  • What are your exact goals? You mention servers in the subject, does that mean this is primarily for keeping a public server available?
    To briefly touch some of your points- BGP requires two business-class connections and getting two ISPs to work together. If you have an expensive connection this may happen, if it's a cheap line, probably not.
    The ISPs will have separate IP space and you can use pfSense to create a redundant/load-balanced connection. Outgoing is fairly easy, incoming has some caveats. CARP is used for hardware redundancy, to keep you running if the firewall has a failure- hard drive, power supply, etc. The secondary node takes over when the primary firewall fails.



  • My goal is to keep public available servers up and running even if
    a) 1 pfSense box dies (carp for this i guess)
    b) one of my isp lines is down.  And a secondary objective is to get increased bandwith by utilizing both connections.

    I know if you have two ISPs with a different IP-space i could easily load-balance outgoing. And perhaps use DNS for incomming "failover". But DNS is too slow to be acceptable in this case i'm afraid.

    I don't have a line yet. So i'm wondering what i should ask for and how i need to implement this. Is BGP the only way?



  • If you need one IP block available through two different ISPs, then yes, you will need BGP.
    There is a reason why critical 24/7 apps are usually hosted in data centers. For less mission-critical uses, you can set the ttl low and shuffle A records. The pfSense DNS package does this, but I have yet to try it out. I'm fond of cheap, low-tech solutions: Let's say you have users who go to orders.company.com to submit orders. Tell them if they can't get to it, to try orders2.company.com.



  • @dotdash:

    If you need one IP block available through two different ISPs, then yes, you will need BGP.
    There is a reason why critical 24/7 apps are usually hosted in data centers. For less mission-critical uses, you can set the ttl low and shuffle A records. The pfSense DNS package does this, but I have yet to try it out. I'm fond of cheap, low-tech solutions: Let's say you have users who go to orders.company.com to submit orders. Tell them if they can't get to it, to try orders2.company.com.

    Ah okay. I guess BGP is pretty complex for a non -cisco/-network guy and probably would create more downtime if I used it vs. if I didn't (poor ability to troubleshoot).

    Multiple dns-records was the initial plan I had and I might just go for it.
    Is it considered "rude" to have a very low TTL?


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