[RndTbl] Main firewall / router for public facing subnet

Alberto Abrao alberto at abrao.net
Tue Mar 31 00:28:25 CDT 2020

That could be a way, but I was more inclined to do it the way I assume - 
and the word is assume, as I have no idea - an ISP like Shaw is doing 
it: they assign addresses that are public facing to machines they have 
no access to, but they filter what goes in and out no problem. As we've 
discussed a few months ago, it's what goes for residential IPs.

It's more about the know how than just getting something that works. I 
really need to step up my networking game. My setup here is nothing more 
than a lab. As far as I know, a managed router would be enough for most 
of my QoS needs, and the firewalls are doing their jobs on the two 
servers (using static IPs) + the internal network router (which grabs a 
residential DHCP address). But that would be too easy, I guess?

And I am totally with you on the difference between small companies' 
requirements (and budgets!) compared to big ones. Hell, I used to set up 
OpenWRT routers with samba shares to replace aging Pentium III boxes 
running XP for Samba duties *AND* the pwned ISP-supplied router that had 
its DNS hijacked, and that was around 2015. The hard disk on that beige 
case alone was on borrowed time...hardcore. Of course most Canadian 
companies don't need to do something that extreme to save a buck, so you 
can order something really nice and get the job done with room to spare, 
ticking all the boxes, right? Nah... I am still SERIOUSLY looked down 
upon when I argue that my solution meet the requirements set, yet cost 
1/10th of what was quoted by an "enterprise" vendor, and I am not even 
exaggerating. There's the solution of the issue and the process of 
selling it, and the more expensive it is, the more enterprisey it 
sounds, right? And THAT'S why I am trying to look pretty... =D

I am not tied to any particular OS, as long as 1) it's open (e.g. not 
Windows) and 2) no GUIs. My plan was to have something that would do QoS 
and, after that is working, study how to move the firewall duties to it.

I must make it clear that I don't expect anyone to walk me through it, 
hold my hand or anything. Some recommended reading would be all it 
takes, even if it's a monster tome. And I can't think of a better place 
to ask for this than here, otherwise I will have tons of people selling 
me Cisco stuff or whatever.

And, once again, thank you everyone for chiming in. I really appreciate it.

Alberto Abrao

On 2020-03-30 11:06 p.m., Trevor Cordes wrote:
> On 2020-03-30 Alberto Abrao wrote:
>> Doing it for a single external IP is manageable to me, the thing is
>> the leap in doing it for multiple public IPs. I do know I have some
>> heavy reading ahead, and I look forward to it. Any recommendations
>> are very much appreciated.
> That part is easier than you think.  I haven't done it yet, mainly
> because I'm too cheap to spring for a plan with multiple statics, but
> I'm pretty sure you'll just set up your single interface to listen on
> multiple IPs.  Then use routing and/or packet-mangling-de-jour methods
> to forward them to the correct internal boxes.  After firewall-checks,
> of course.
> Easy for statics, but you might not be able to do more than 1 of your
> DHCP dynamic on that interface, though??  Unless you can setup a 2nd
> "fake" MAC on the same interface?  Others can chime in.
>> I used to do one-box-for-everything as well, mostly because I didn't
>> have a lot of equipment to begin with. However, I see lots of people
>> talking about security, and I can see having things on separate
> I'm of the opinion that if you're a wizard it really doesn't matter if
> it's all one box or not.  If they p0wn your firewall, chances are
> they'll then hop into whatever internal, less protected, box they want
> anyhow without much trouble.  The key is to not get p0wned.  I'm talking
> from a personal and micro-business standpoint: for corporate of course
> you'll want to throw money at separating everything.
> It's hard enough, and expensive enough, trying to keep X quality (read:
> ECC) boxes going, let alone X+1 boxes (and more +1's for every new
> task).  I'd rather have 1 boss ECC system that I know won't give me
> grief do everything than a handful of cheap / small / esoteric boxes
> (probably with no ECC).  It's my philosophy.  I understand it's not
> shared by the writers of best practices.  YMMV.
> If you've already learned OpenBSD and like it, of course stick with it,
> unless you've hit limitations.  As for iptables vs pfsense, I've yet to
> run into a scenario tc/iptables/etc can't do, and I do some pretty
> wacky esoteric stuff on many boxes.  However, here's a great example of
> why you'd like Fedora rather than CentOS: the newer, handy iptables
> features are generally bleeding edge and only to be found in distros
> that give you the bleeding kernel.  If you're on the typical
> multi-year-old RHEL kernel then you may find that what you want to do
> isn't possible.

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