Re: New Office, New Network. Questions.

[alvin nanog <nanogml () Mail DDoS-Mitigator net>]

hi nikolai

- oops.. this got long based on my experiences/opinions :-)

On 07/10/16 at 09:53pm, Nikolai Petrov wrote:
> We are moving to our new offices in two months and I have access to the building already.
> My task is to set up the entire network for the company.
> The previous administrator has left the company and I thought of taking the chance to remove some "technical debt" 
> and make everything from scratch again.

all good ... 

> I was told to move the networks this week 

do you have the routers, switches, cables, few servers for testing ?
has your ISP installed their internet uplink connectivity to the bldg ?

if so, than the above management is on their toes 
otherwise, you'd need to rattle some $$$ loose to buying missing hw :-)

> and I have spent a lot of time thinking about how I should do it.

good ... now's the chance to fix the problems if any ..

> 1. Currently we do not have IPv6 in our network 

implies a learning IPv6 curve ( red flag for possible time-wasting hogs )

if the task is to mvoe the entire "mid-sized" from current bldg to new bdlg, 
i'd suggest use "known/good/working/best-practices" methodology to move
the company.  first get the new bldg with new test servers working
with IPv4 ( the way you want it done ) and "working" the current bldg 
which should take a few hours :-)

than work with IPv6 issues 

> but I have seen the ISP is giving us a "/56 Block" 

good

> which from what I understand is a couple hundred "/64 Subnets".
> I think you can only have /64 subnets in IPv6.

nah ... you can subnet your /56 into whatever you want

> In our IPv4 setup we have 32 addresses,
> four of which I will use for NAT 
> and the remaining needed for online services and servers.

good ... use that to test everything 

since you want or going to use NAT, you have the standard
internal LAN for the bldg can use the standard 10/8 or 
192.168/16 or 172.16/12

so far.. nothing new/special/problematic

> In IPv6 we have a lot of addresses but I am not sure whether 
> I should give an address of the ISP to every device.

why would you want to complicate time-restricted ( 1month )
to get the new bldg working with IPv6 w/out having prior
IPv6 experience ?

remember, "all eyes" will be looking to you to move the
whole company from current bldg to new bldg without delay

> I found that there is an organization that can help avoid collisions 
> in private IPs: https://www.sixxs.net/tools/grh/ula/ .

there should never be any collision in IP#, ipv4 or ipv6

>  From what I can tell it is just a registry, but I am thinking of 
> registering the ranges there and then use these subnets and 
> NAT them to the IPv6 address of the router.

the ISP provides you the range of IPv6 assigned to you

if your current bldg does NOT have IPv6, you might not be
able to easily test the new IPv6 stuff in the new bldg

you might be able to test your new IPv6 connections
at the local coffee shop or other public places but
that's a major security violation since your new IPv6
has no security pre-cautions installed yet

you should be paranoid about trojans/worms/mailware piggie
backing into your new un-secured new bldg IPv6 infrastructure
or IPv4 infrastructure

> However, I noticed something strange. The WAN port of our
> router gets a /64 IPv6 address which is not in our IPv6.

why strange ??

routers get its IP# from dhcpv6 or statically  assigned

> Should I use this for NAT or one of "our" addresses?

you need to fix this problem before continuing .. 
( explain why the IPv6/64 is not what you're expecting )

NAT is NOT the solution ...

> 2. The previous administrator did some bad job in some parts of the network.

:-) that will always be true 90% of the time :-)

some things are always gonna be "bad"

> We have an internal router protocol to move traffic between routers, 
> but in some cases he used NAT instead of adding these subnets to the 
> router protocol. Everything works and all things that have to be 
> reached are reachable, 

if it works .. why is is "bad" ??

there might be dozens of different ways to make things work 
( "things that have to be reachable are reachable" )

> however I think this is bad 

not necessarily a bad thing

> and we should use the router protocol for all parts of the network.

why ?

> I have found two protocols in our router that are good and support 
> IPv6 and they are OSPF and BGP.

there might be more :-)

>  I did not manage to have BGP work 

what part is not working ?

google/yahoo the error messages :-) 

> and it is slow so I am thinking of OSPF. 

sometimes, which works first/better/easiest might be
a good option, thus trying other things is good, but
that can also create more headaches too .. more problems
to (fun) solve

> Do uou think it is a good choice for IPv6 and IPv4? 

i'd work with IPv4 first ... 
and more importantly... there is NO excuse why IPv4 doesn't
or cannot work in the new bldg

after IPv4 works in the new bldg as good as it does in the current
bldg, you have time for "( IPv6 ) learning experiements"

> If I have two separate paths of 1 Gb/s, will I transfer files at 2 Gb/s?

no ... you will be able to transfer 1Gb/s each ..

if you "channel bond" the two 1Gb/s into "one link",
than you might be able to see 1.9Gb/s uplinks .. never 2G/s

if you have 2 1G/s uplinks ... you should have the 2 routers
crosslinked for failover unless uplink speed is more
important than failover

> 3. In our old network we use "VRRP" which from what I know 
> is a system for routers to shae IPs and load balance or "failover" the traffic.

good

> I have seen that IPv6 has a built-in system which is similar 
> and has something like priorities, etc. What happens if I have 
> two routers with same priority?

same rules/issues apply to IPv4

one router/path should always have priority over the other
depending on destinations .... lots of testing to see which
packets goes thru which uplinks

> Whic is used as default gateway?

depends..

engineering/manufacturing uses router1
hr/accting uses router2

or

public DMZ uses router1
corp LAN uses router2

but in either case, router1 and rotuer2 should be crosslinked
if failover is important

> Is it load balancing? Also, can I use "VRRP" to load balance traffic
> to our DNS look-up "recursor"? 

dozen ways to do load balancing ... more problems to resolvea
and prioritize based on your company visibility online

load balancing should be worried about:
- dns, www traffic, email traffic, DVD/video/music downloading,

also always have 3 hot-swap complete infrastrucure and backups
fw1 + dns1 + www1 + mail1 + NAT1
fw2 + dns2 + www2 + mail2 + NAT2
fw3 + dns3 + www3 + mail3 + NAT3

fw only runs iptables for inline fw for entire dmz/localLan
dns only runs bind and iptables and nothing else
www only runs apache and iptables and nothing else
mail only runs sendmail and iptables and nothing else
nat only runs NAT + iptables

each backup its bind/sendmail/apache data to the other 2 boxes, but 
bind/sendmail/apache itself is turned off on the other hot backups

magic pixie dust
alvin
#
# DDoS-Mitigator.net
#