Intermittent connection issue

kevindd992002

@johnpoz said in Intermittent connection issue:

The different with dnsmasq and unbound for forwarding is dnsmasq out of the box forwards to ALL of the forwarders you have set at the same time, and uses just uses the first answer. I don't think you can tell unbound to do that.. Would have to check the unbound docs - but there is no way to set that in the gui of pfsense. This can be good for when you have bad peering isp or issues talking via some paths, etc.

Well restarting unbound never helps because it flushes your cache. But you do have a lot of timeouts you showed - so something not great with your isp either which could be problems.

For all we know your isp connections has gotten better, and has zero to do with unbound restarting.

Again when you have issues with dns - you can not just assume the problem is X, you need to troubleshoot the exact issue your seeing... Not just dns not working sometimes.. Pick something that didn't work and find out why.. Are you still seeing a lot of timeouts in your infra info?

You can also make sure you setup prefetch with unbound, this can help with problematic issues because it will look up stuff in the background before the ttl expire and it flushes out of the cache. Also setting serve 0 ttl can really help as well. Since now even if the cache expired, it would serve up the last entry when client asks for it - and then look it up in the background again.

@johnpoz

Does this mean that unbound, by default, when set to forwarding mode queries the DNS servers you set in General sequentially and that you cannot change this behavior?

bjohe

@kevindd992002 and @johnpoz
This is my understanding from the documentation. "unbound will use the system DNS servers from System > General Setup or those received from a dynamic WAN, rather than using the root servers directly"

When I changed my DNS resolver setting to "Enable Forwarding Mode" most of my intermittent connection issues have disappeared. Sometimes I still have to wait a sec or two before the webpage loads completely, but In general the pages load immediately and there are no long periods of total non-connection.

I have not tried using the DNS Forwarder (dnsmasq). The documentation on “DNS Query Forwarding” mentions that DNSSEC need to be disabled but I have not done this. Maybe it works for me as I did check that the DNS servers I choose were supporting DNSSEC.

kevindd992002

I don't see any GUI setting for DNSSEC in dnsmasq so I'm not sure if it's supported. But yeah, if my upstream DNS server is just the ISP modem anyway (double NAT config), I won't use the "simultaneous query of DNS servers" capability of dnsmasq. In that case, would staying with unbound and forwarding be advisable since it has DNSSEC support and other settings that you can customize?

kevindd992002

@johnpoz Do you still have any ideas on my question?

kevindd992002

Just an update to this issue:

My ISP had my account migrated to their VLAN for static (public) IP configs for two weeks testing and I had 0 problems with unbound (resolver). As soon as they transferred me back to using dynamic IP with CGNAT, the issue went back right away when using unbound (resolver). I had to go back to using unbound (forwarder) again as a workaround.

They wanted me to switch over to using static IP but to do that I would have to upgrade my subscription with them and pay the extra static IP subscription. That won't happen. I'm trying to fight with them now and convince them that the issue is with their dynamic IP network.

Gertjan

Not being able to use the default resolver, unbound, in resolving mode means a severe connection problem.
Very standard DNS data traffic is one of the basic Internet minimal requirements.

kevindd992002

Exactly. That's what I've been telling them. DNS traffic is nothing special. It's like they're forcing their customers to only forward DNS requests.

Gertjan

@kevindd992002 said in Intermittent connection issue:

It's like they're forcing their customers

They discovered, like many before, that that info is worth a max. People are using already themself's massively the "let bring everything to 8.8.8.8".
And lets face it : if you are an ISP, and you have to make this deal with nearby Google's data centre to invest in a very costly 50 / 50 % fiber POP between the Google data centre and the ISP centre (ISP users consume a LOT of Youtube traffic !!) then what should this ISP do ? They cash cash out or they 'make this another deal'.
So, yes, DNS is manly 'visible' to they can grab it, and do what they want with it.

Btw : it's the technical point of views that interests me here. I don't care what Google does, neither my ISP. They can have it, I don't care.

johnpoz

Get a different ISP? Clearly you pointed out them that their carrier grade nat is broken..

kevindd992002

@Gertjan said in Intermittent connection issue:

@kevindd992002 said in Intermittent connection issue:

It's like they're forcing their customers

They discovered, like many before, that that info is worth a max. People are using already themself's massively the "let bring everything to 8.8.8.8".
And lets face it : if you are an ISP, and you have to make this deal with nearby Google's data centre to invest in a very costly 50 / 50 % fiber POP between the Google data centre and the ISP centre (ISP users consume a LOT of Youtube traffic !!) then what should this ISP do ? They cash cash out or they 'make this another deal'.
So, yes, DNS is manly 'visible' to they can grab it, and do what they want with it.

Btw : it's the technical point of views that interests me here. I don't care what Google does, neither my ISP. They can have it, I don't care.

But I don't forward to 8.8.8.8. I'm trying to resolve. Sorry, not sure what you mean?

@johnpoz said in Intermittent connection issue:

Get a different ISP? Clearly you pointed out them that their carrier grade nat is broken..

I can't, I'm still locked in with them (contract) and I have a point-to-point VPN connection with my other house that's using the same ISP (so best connection quality).

Gertjan

@kevindd992002 said in Intermittent connection issue:

But I don't forward to 8.8.8.8

8.8.8 is just an example. And I was talking about 8.8.8.8, choosen by your ISP, the DNs where they are forwarding to.

@kevindd992002 said in Intermittent connection issue:

I had to go back to using unbound (forwarder) again as a workaround.

To who ?

Sending DNS request to

Hostname 	IP address IPv4 / IPv6 	Organization
a.root-servers.net 	198.41.0.4, 2001:503:ba3e::2:30 	VeriSign, Inc.
b.root-servers.net 	199.9.14.201, 2001:500:200::b 	University of Southern California (ISI)
c.root-servers.net 	192.33.4.12, 2001:500:2::c 	Cogent Communications
d.root-servers.net 	199.7.91.13, 2001:500:2d::d 	University of Maryland
e.root-servers.net 	192.203.230.10, 2001:500:a8::e 	NASA
f.root-servers.net 	192.5.5.241, 2001:500:2f::f 	Internet Systems Consortium, Inc.
g.root-servers.net 	192.112.36.4, 2001:500:12::d0d 	US Department of Defense (NIC)
h.root-servers.net 	198.97.190.53, 2001:500:1::53 	US Army (Research Lab)
i.root-servers.net 	192.36.148.17, 2001:7fe::53 	Netnod
j.root-servers.net 	192.58.128.30, 2001:503:c27::2:30 	VeriSign, Inc.
k.root-servers.net 	193.0.14.129, 2001:7fd::1 	RIPE NCC
l.root-servers.net 	199.7.83.42, 2001:500:9f::42 	ICANN
m.root-servers.net 	202.12.27.33, 2001:dc3::35 	WIDE Project

or, the DNS you choose to forward to, what is the difference ? Yet you said that the first 13 are not possible.

Read, for example https://securitytrails.com/blog/dns-root-servers and understand something is very wrong.

Reset pfSense to default, and see if it works. If not, take a look at your ISP contract.

@kevindd992002 said in Intermittent connection issue:

I have a point-to-point VPN connection

Aha. That changes a lot.
Use pfSense with default settings (again !) and the resolver will work.
Adding a VPN and suddenly it stops. That make the solution rather simple. : remove things that break things.
Or setup correctly the new things.

kevindd992002

@Gertjan said in Intermittent connection issue:

@kevindd992002 said in Intermittent connection issue:

But I don't forward to 8.8.8.8

8.8.8 is just an example. And I was talking about 8.8.8.8, choosen by your ISP, the DNs where they are forwarding to.

@kevindd992002 said in Intermittent connection issue:

I had to go back to using unbound (forwarder) again as a workaround.

To who ?

Sending DNS request to
Hostname 	IP address IPv4 / IPv6 	Organization
a.root-servers.net 	198.41.0.4, 2001:503:ba3e::2:30 	VeriSign, Inc.
b.root-servers.net 	199.9.14.201, 2001:500:200::b 	University of Southern California (ISI)
c.root-servers.net 	192.33.4.12, 2001:500:2::c 	Cogent Communications
d.root-servers.net 	199.7.91.13, 2001:500:2d::d 	University of Maryland
e.root-servers.net 	192.203.230.10, 2001:500:a8::e 	NASA
f.root-servers.net 	192.5.5.241, 2001:500:2f::f 	Internet Systems Consortium, Inc.
g.root-servers.net 	192.112.36.4, 2001:500:12::d0d 	US Department of Defense (NIC)
h.root-servers.net 	198.97.190.53, 2001:500:1::53 	US Army (Research Lab)
i.root-servers.net 	192.36.148.17, 2001:7fe::53 	Netnod
j.root-servers.net 	192.58.128.30, 2001:503:c27::2:30 	VeriSign, Inc.
k.root-servers.net 	193.0.14.129, 2001:7fd::1 	RIPE NCC
l.root-servers.net 	199.7.83.42, 2001:500:9f::42 	ICANN
m.root-servers.net 	202.12.27.33, 2001:dc3::35 	WIDE Project
or, the DNS you choose to forward to, what is the difference ? Yet you said that the first 13 are not possible.

Read, for example https://securitytrails.com/blog/dns-root-serversand understand something is very wrong.

Reset pfSense to default, and see if it works. If not, take a look at your ISP contract.

@kevindd992002 said in Intermittent connection issue:

I have a point-to-point VPN connection

Aha. That changes a lot.
Use pfSense with default settings (again !) and the resolver will work.
Adding a VPN and suddenly it stops. That make the solution rather simple. : remove things that break things.
Or setup correctly the new things.

I'm currently forwarding to another local ISP's DNS servers that's known to be more stable. This works fine. As soon as I use resolver (querying against root hints servers), I get random drops. Are you saying ISP themselves just forward to Google for example? I was under the impression that they act as a resolver.

The link you gave is not found.

If you remember, we've been over the resetting of things to defaults :) It doesn't work. What I've been able to deduce/conclude is what I've explained just recently (resolver vs forwarder).

Not sure how a point to point VPN connection affects this? DNS traffic isn't routing through the tunnel. Also, like I said I did try pfsense with default settings already, to no avail. With a static IP from the ISP, everything works as expected. So there's really something wrong with their dynamic IP VLAN.

johnpoz

@kevindd992002 said in Intermittent connection issue:

I was under the impression that they act as a resolver.

You have no idea what they do.. They could resolve, they could forward... You threw your dns over the fence to them - what they do with it is out of your control... You just hope they give you back an answer, and you trust them to give you good info... They could give you whatever they want..

This is one of the big advantages to resolving - you control the dns.. You ask the authoritative NS directly... Not just trust someone else to have the right answer.

For all you know they forward, and the person they forward to forwards ;) Yes at some point there has to be a resolver.. But it could be a couple of forwarders in there for sure..

kevindd992002

@johnpoz said in Intermittent connection issue:

@kevindd992002 said in Intermittent connection issue:

I was under the impression that they act as a resolver.

You have no idea what they do.. They could resolve, they could forward... You threw your dns over the fence to them - what they do with it is out of your control... You just hope they give you back an answer, and you trust them to give you good info... They could give you whatever they want..

This is one of the big advantages to resolving - you control the dns.. You ask the authoritative NS directly... Not just trust someone else to have the right answer.

For all you know they forward, and the person they forward to forwards ;) Yes at some point there has to be a resolver.. But it could be a couple of forwarders in there for sure..

Exactly! I want to have my own resolver. I told them that I don't want to rely on their DNS servers.

Gertjan

@kevindd992002 said in Intermittent connection issue:

Are you saying ISP themselves just forward to Google for example?

Well. Yes.
I don't know what they do, as they don't tell me, and I did not asked them.
But what would you do, being an ISP - and you have to pay the POP's ?
Resolve ? Or use Google DNS and billing them with thousands every month ? or not paying that POP thousands a month ?

Again, you should be able to 'contact' the main 13 first core DNS servers. If not, something is very wrong.

kevindd992002

@Gertjan said in Intermittent connection issue:

@kevindd992002 said in Intermittent connection issue:

Are you saying ISP themselves just forward to Google for example?

Well. Yes.
I don't know what they do, as they don't tell me, and I did not asked them.
But what would you do, being an ISP - and you have to pay the POP's ?
Resolve ? Or use Google DNS and billing them with thousands every month ? or not paying that POP thousands a month ?

Again, you should be able to 'contact' the main 13 first core DNS servers. If not, something is very wrong.

I am able to contact the root hints servers but they're randonly dropping traffic, as if they're traffic shaping or something. Oh well, I'm still making them have a hard time about this.