Network/routing issue within bt core network?

[#1]

Hi, I have a ticket open since Tuesday regarding thsi, unfortunately still experiencing the issue and zero progress on the ticket.  Can someone help ping an IP (via PlusNet network) to help narrow down this problem please?

Basically pretty much bang on midnight Tuesday (00:00 9th July) access to https://proshipping.royalmail.com is no longer responding via my Plusnet connection. The trace stops around ukcore.bt.net routers.

#mtr -c 5 --report proshipping.royalmail.com

HOST                                    LOSS  RCVD SENT    BEST     AVG   WORST

192.168.1.254                             0%     5    5    0.68    0.70    0.73

254.core.plus.net                         0%     5    5    9.12    9.45   10.04

84.93.253.119                             0%     5    5    9.71    9.93   10.02

195.99.125.138                            0%     5    5    9.63    9.84   10.09

core5-hu0-4-0-26.faraday.ukcore.bt.net    0%     5    5   10.29   10.56   10.71

core1-hu0-2-0-2.colindale.ukcore.bt.net    0%     5    5   10.08   10.31   10.59

acc3-hu0-0-0-0.colindale.ukcore.bt.net    0%     5    5   10.23   10.43   10.77

217.38.123.105                            0%     5    5   12.92   13.10   13.23

                                     100%     0    5    0.00    0.00    0.00

I can ping this IP (157.203.59.48) from other providers and networks I have access to, and a colleague on a BT full fibre connection says no issue and a similar (but not identical) route.

Royal Mail say nothing changed at their side and the service is responding ok (which I guess is true but they didn't/can't ping back to my IP to highlight routing issues) but I am still unable to get any response from that IP (or 157.203.59.49 which is another one)

It feels given the timing that this was a scheduled update to a router somewhere, but that's hardly conclusive!

Not experiencing any other connectivity issues to other sites either.

Is anyone able to see if this IP/web address is pingable via their PlusNet connection as I don't have any other means to check.

[#2]

Could this be related to another issue here?

In both cases I can't access the site on my PN connection but can on my wife's PN connection in the same building.

[#3]

Thanks, suppose it's possible as it looks like same IP block.

What's the difference between traceroutes on those two connections, if you please, or is the difference the allocated IP of the PN connection (pointing to an outbound routing issue FROM the sites concerned)?

Not sure how to get this progressed to be honest, supposedly the ticket was raised to the 'service desk' but no updates or resolution seems forthcoming, and it's pretty much a P1 issue when connectivity/routing is as such 😕

[#4]

---

@Mav wrote:

Could this be related to another issue here?

---

I posted in that other thread as I'm seeing the same on an EE connection for the NS&I issue. FWIW, I can access the Royal Mail URL without issue.

[#5]

...I can't! 

[#6]

Is your IP address in the 84.92.192.0 range? Can check with whatismyip.com 

inetnum: 84.92.192.0 - 84.92.255.255
netname: PLUSNET-DIAL-ADSL
descr: Dial-up and ADSL pool
descr: PlusNet Technologies Ltd
country: GB
admin-c: PLUS1-RIPE
tech-c: PNET2-RIPE
status: ASSIGNED PA
mnt-by: MAINT-AS6871

[#7]

I too can't access the Royal Mail site above, PN Fixed IP in the 212.159 range.

Already confirmed no access to the NS&I** via the same connection in the NS&I thread.

Edit: ** via the links in question in that thread.

[#8]

This is still unreachable, though NS&I login page was fixed a couple of hours ago this afternoon.

[#9]

During this, I've been able to access the NS&I website *and* the RM website (screenshot attached).

[#10]

I get an IP assigned from a /24 block (possibly /23, but the addresses in the whole /23 appears to have disappeared in the past 4-5 months?) which appears to be 'pinned' to FTTP provision, possibly within a restricted area.

[#11]

Maybe somebody needs to write a letter to Royal Mail?

Just saying... 🤣

[#12]

Just an update - it appears that the network connectivity issue to 157.203.59.48/49 was resolved around 13:40 BST today Tue 23rd July 2024.

# mtr -c 5 --report proshipping.royalmail.com
HOST LOSS RCVD SENT BEST AVG WORST
192.168.1.254 0% 5 5 0.71 0.76 0.93
254.core.plus.net 0% 5 5 7.58 10.66 15.62
84.93.253.115 0% 5 5 8.36 8.53 8.86
core1-BE1.southbank.ukcore.bt.net 0% 5 5 8.31 8.47 8.72
core5-hu0-4-0-26.faraday.ukcore.bt.net 0% 5 5 8.79 9.10 9.34
core1-hu0-2-0-2.colindale.ukcore.bt.net 0% 5 5 8.75 9.05 9.57
acc3-hu0-0-0-0.colindale.ukcore.bt.net 0% 5 5 9.09 9.27 9.59
217.38.123.105 0% 5 5 11.56 11.64 11.71
100% 0 5 0.00 0.00 0.00
100% 0 5 0.00 0.00 0.00
100% 0 5 0.00 0.00 0.00
100% 0 5 0.00 0.00 0.00
157.203.59.48 0% 5 5 17.07 17.52 18.58

The outbound network routing path appears the same so it feels like the return path was indeed the issue and subsequently corrected. Maybe a gateway router change within ATOS network - suggested by the fact that the NS&I issue was resolved last week yet on the same subnet - only other explanation is a firewall block that was inadvertently set. If there was an upstream BGP route issue the entire block would have been fixed not just NS&I and RM a week later (except where NS&I changed gateway to another non-faulty router as a workaround and RM didn't). Final option could be that RM still hasn't made any change and the faulty router has now been fixed - you would hope/imagine there's HSRP or similar router failover/redundancy in place.

I'm a bit annoyed by NS&I suggesting Plusnet blocked access (168bill's complaint response in the other thread) - if that were the case then surely traceroutes would not have had any response from hops outside of Plusnet's remit, and also there would have been no legitimate reason to do so! I think that complaint response is worthy of a complaint, clearly an unevidenced claim!

[#13]

@kehall I suspect it more a standard 'we are the Government, we can do no wrong' response, but they will never admit it - your detailed examination points clearly to something deeper in the system.

[#14]

Faulty blade on a router (firmware faults)? Sometimes they come in clusters, and you join the queue for the replacement blade. Major multinational companies come behind the tiers of international networking providers.

Given that some haven't had problems, I'm almost suspecting some sort of MLS 'issue'.

You would really need access to all the routers (and their various 'tables') to come to a defintive answer. IMO.

[#15]

It's on the 'other' board (NS&I).

Here it is: Re: Can't reach NS&I login page - Page 16 - Plusnet Community