arun Try this on Mac OS X...

sudo /bin/sh -c "$(curl -s https://nextdns.io/diag)"

This will prompt you to enter your sudo password. 

Olivier Poitrey 

Somewhat off topic, but just to point out that I think the ‘copy’ button (which is a nice feature of the template you’re using) seems to introduce those problematic characters, at least on iOS. If I copy manually by selecting the characters on screen it works fine, but if I use the copy button to the right of the code block I get the same error as above. Not sure if the template is at fault or just the page. 

Olivier Poitrey macOS Big Sur 11.1

Olivier Poitrey Yes, I've tried multiple times, even after your last reply. I keep getting the same error, with one change. The number in the /tmp/nextdns-diag-nnnn keeps changing on every try.

Olivier Poitrey 

Darwin redacted.local 20.2.0 Darwin Kernel Version 20.2.0: Wed Dec  2 20:40:21 PST 2020; root:xnu-7195.60.75~1/RELEASE_ARM64_T8101 arm64

Olivier Poitrey Hi, I ran the test using an Intel Mac and while the test completed, it gave a bunch of errors within and towards the end.

Fetching PoP name for primary IPv4 (45.90.28.0)
Fetch error: Get "https://dns.nextdns.io/info": dial tcp 45.90.28.0:443: connect: operation timed out
Fetching PoP name for secondary IPv4 (45.90.30.0)
  anexia-ams: 130.003ms
Fetching PoP name for primary IPv6 (2a07:a8c0::)
Fetch error: Get "https://dns.nextdns.io/info": dial tcp [2a07:a8c0::]:443: connect: operation timed out
Fetching PoP name for secondary IPv6 (2a07:a8c1::)
  anexia-ams: 135.585ms

and towards the end

Post unsuccessful: status 400
{"error":"0: instance requires property \"Primary\"\n"}%

Olivier Poitrey Hi, any plans on adding native support for the official app (on the Appstore) and to the diag tool for M1 architecture. Currently, to enable system wide DNS I am using the CLI of NextDNS on my M1 Mac which seems to be working without a hitch! :)

Olivier Poitrey thansk for great service and foudn myh slow down it was with myh network switch got new one works great now with you and i send, you a email think yhou need to look at it right a way not for forums at all thanks ray toth it came from my gmail email thansk

Olivier Poitrey Yes the message " environment: line 85: detect_endiannes: command not found " is bow gone :) 

https://nextdns.io/diag/f6c89670-42a5-11eb-9999-db30abba5b99

Steen

replying my own post: seems to be related to Little Snitch. Also throwing other errors. Posted an issue on GH (https://github.com/nextdns/diag/issues/11).

Khairul Are you using a DNS server (either on your phone or at the router level) that's in the US?

Romain Cointepas I'm using both DoT (Private DNS for Android 9+) and Android below than Android 9, I'm using DoH in Chrome. Ya that's from US server. My ISP is AS4788 (Malaysia). I'll put result from test.nextdns.io for your reference.

Romain Cointepas and this result from ping.nextdns.io

Khairul The reason you're being sent to US servers with NextDNS is that the DNS server in your network (what's used to first resolve dns.nextdns.io) is something hosted on Amazon AWS in the US (3.18.127.41). My guess is down the line on your network, a custom US DNS server is set?

Romain Cointepas oh i see, you right!.. I don't know thats my dns on my router affect nextdns ultralow route, because I just want to use nextdns on my portable devices but not on my home router. Thank for your support

Romain Cointepas for your information when I change back to cloudflare dns and enable IPv6, ultralow changed.. not US anymore...

Khairul Can I ask what DNS server you use on your router, and why is it in the US when you are in Malaysia?

Romain Cointepas https://alternate-dns.com/ they just upgraded their infrastructure, hosted by Amazon AWS (I guess) which is fast in my country (routed to Amazon Singapore). Idk thats affect my NextDNS DoT and DoH on my phone. So I changed back to Cloudflare.

Khairul is NextDNS routing better when using Cloudflare on the router?

Romain Cointepas https://nextdns.io/diag/ab23db60-7394-11eb-8d0e-4bbc5409628a

Yeah all route to Singapore (IPv4 & IPv6), except anycast2 route to London (IPv4 & IPv6). I think it would be nice if you can fix anycast2 route maybe? But I don't think it will be used in my case because I'm using DoT and DoH which is NextDNS using ultralow I guess. Maybe some other user from my ISP use unencrypted DNS from NextDNS. It would be good if anycast2 (both IPv4 & IPv6) are faster too.

John DeCarlo you and me both have same Anycast DNS issue. Hopefully it gets fixed soon! 

John DeCarlo 

Consistent  with mine: 

i am also on TWC-11351-NORTHEAST

Secondary: anexia-jnb (297 ms)

Secondary IPv6: anexia-jnb (270 ms)
 

TheGreat1G  it’s fixed now, thank you! No more pings to Africa Johannesburg

Olivier Poitrey I would like to, but it's stuck on a traceroute (like https://github.com/nextdns/diag/issues/3)

Olivier Poitrey Okay, it worked from another device: https://nextdns.io/diag/73ccd2c0-89d3-11eb-9842-b351f7e87eda

However I have been getting less packet loss for half an hour. I should try a diag again when it's back.

Olivier Poitrey I do have other smokeping probes that do not display any loss: https://imgur.com/a/Tv1S8yZ

Olivier Poitrey It seems to be better (so far)

I had some latency spikes last night without loss, during which I run a mtr (ipv6):
 

 Host                                                          Loss%   Snt   Last   Avg  Best  Wrst StDev
 1. livebox.home                                                0.0%   156    1.0   1.2   0.9   5.9   0.6
 2. xxx.ipv6.abo.wanadoo.fr                                     0.0%   155    2.6   2.6   1.5  11.4   1.2
 3. 2a01:cfc4::b                                                0.0%   155    3.7   4.2   2.4  67.0   6.1
 4. bundle-ether104.pastr4.paris.opentransit.net               98.7%   155    3.4   3.0   2.6   3.4   0.6
 5. ae-26.r04.parsfr01.fr.bb.gin.ntt.net                        0.0%   155   26.8  29.3  24.0  53.1   3.2
 6. xe-0-6-0-2-1.r04.parsfr01.fr.ce.gin.ntt.net                 0.0%   155   28.1  31.0  23.2  88.6  10.1
 7. dns.nextdns.io                                              0.0%   155   29.0  28.3  22.7  38.2   2.1

We'll see how it will evolve in the next few days

It's not better.

https://nextdns.io/diag/5936d510-bbe6-11eb-b41c-7b3bf0a2ed4c