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Re:"Out of Band" network management is not trivial by Scoundreller on Sunday July 07, 2024 @02:39AM (#40895726)
One thing that was fascinating about the Rogers outage was on the wireless side: because "just" the core was down, the towers were still up.

So mobile phones would try to make a connection to the tower just enough to connect but not be able to do anything, like call 9-1-1 without trying to fail-over to other mobile networks. Devices showed zero bars, but field test mode would show some handshake succeeding.

(The CTO was roaming out-of-country, had zero bars and thought nothing of it... how they had no idea an enterprise-risking update was scheduled, we'll never know)

Supposedly you could remove your SIM card (who carries that tool doohickey with them at all times?), or disable that eSIM, but you'd have to know that you can do that. Unsure if you'd still be at the mercy of Rogers being the most powerful signal and still failing to get your 9-1-1 call through.

Rogers claimed to have no ability to power down the towers without a truck-roll (which is how another aspect where widespread OOB could have come in handy).

Various stories of radio stations (which Rogers also owns a lot of) not being able to connect the studio to the transmitter, so some tech went with an mp3 player to play pre-recorded "evergreen" content. Others just went off-air.

https://www.theregister.com/2022/07/25/canadian_isp_rogers_o...

Re:"Out of Band" network management is not trivial by wannacboatmovie on Sunday July 07, 2024 @04:07AM (#40895982)
> Supposedly you could remove your SIM card (who carries that tool doohickey with them at all times?)

In sane handsets (ones where the battery is still removable), that tool was and still is a fingernail, which most have on their person.

I believe the innovation of the need for a special SIM eject tool was bestowed upon us by the same fruit company that gave us floppy and optical drives without manual eject buttons over 30 years ago.

Re:"Out of Band" network management is not trivial by rzzzt on Sunday July 07, 2024 @04:52AM (#40896146)
You could operate the ejection mechanism by hand both on optical and floppy disk drives with an uncurled paperclip (or a SIM card ejection tool were they to exist at that point in time). But I wouldn't ascribe the introduction of the motorized tray to the fruit company, it was the wordmark company: https://youtu.be/bujOWWTfzWQ
Re:"Out of Band" network management is not trivial by amluto on Sunday July 07, 2024 @07:40PM (#40901406)
I have fond memories of the fruit company taking the next step: removing the floppy drive bezel from the drive and instead having the floppy drive slot be part of the overall chassis front panel. Of course, their mechanical tolerances were nothing like they are today, so if you looked at the computer crosseyed, the front panel would fail to align to the actual internal disk path, and ejecting the disk would cause it to get stuck behind the front chassis panel. One could rescue it by careful wiggling with a tool to guide the disk through the slot or by removing the entire front panel.

Meanwhile “PCs” had a functional but ugly rectangular opening the size of the entire drive, and the drive had its own bezel, and imperfect alignment between drive and case looked a bit ugly but had no effect on function.

(I admit I’m suspicious that Apple’s approach was a cost optimization, not an aesthetic optimization.)

Re:"Out of Band" network management is not trivial by pgraf on Sunday July 07, 2024 @05:46AM (#40896349)
Sounds like a problem that should be (rather easily) fixable in the Operating System, no?

If the emergency call doesn’t go through, try the call over a different network. This would also mitigate problems we see from time to time where emergency calls don’t work because the uplink to the emergency call center was impacted either physically or by a bad software update.

Re:"Out of Band" network management is not trivial by Scoundreller on Sunday July 07, 2024 @06:21AM (#40896471)
Yes, seems to be a deficiency in the gsm spec as this affected most/all devices.

I didn’t think this failure mode was even possible.

Re:"Out of Band" network management is not trivial by sidewndr46 on Sunday July 07, 2024 @10:01AM (#40897811)
Very few phones have the calls handled by the OS. It usually is handled by something called the baseband, which is more like firmware
Re:"Out of Band" network management is not trivial by throw0101d on Sunday July 07, 2024 @07:19AM (#40896784)
> (The CTO was roaming out-of-country, had zero bars and thought nothing of it... how they had no idea an enterprise-risking update was scheduled, we'll never know)

How does one know ahead of time if any particular change is "enterprise-risking"? It appeared to be a fairly routine set of changes that were going just fine:

> The report summary says that in the weeks leading up to the outage, Rogers was undergoing a seven-phase process to upgrade its network. The outage occurred during the sixth's phase of the upgrade.

* https://www.cbc.ca/news/politics/rogers-outage-human-error-s...

It turns out that they self-DoSed certain components:

> Staff at Rogers caused the shutdown, the report says, by removing a control filter that directed information to its appropriate destination.

> Without the filter in place, a flood of information was sent into Rogers' core network, overloading and crashing the system within minutes of the control filter being removed.

* Ibid

> In a letter to the CRTC, Rogers stated that the deletion of a routing filter on its distribution routers caused all possible routes to the internet to pass through the routers, exceeding the capacity of the routers on its core network.

* https://en.wikipedia.org/wiki/2022_Rogers_Communications_out...

> Rogers staff removed the Access Control ListFootnote 5 policy filter from the configuration of the distribution routers. This consequently resulted in a flood of IP routing information into the core network routers, which triggered the outage. The core network routers allow Rogers wireline and wireless customers to access services such as voice and data. The flood of IP routing data from the distribution routers into the core routers exceeded their capacity to process the informationFootnote 6. The core routers crashed within minutes from the time the policy filter was removed from the distribution routers configuration.

* https://crtc.gc.ca/eng/publications/reports/xona2024.htm

These types of things happen:

> In October, Facebook suffered a historic outage when their automation software mistakenly withdrew the anycasted BGP routes handling its authoritative DNS rendering its services unusable. Last month, Cloudflare suffered a 30-minute outage when they pushed a configuration mistake in their automation software which also caused BGP routes to be withdrawn.

* https://www.kentik.com/blog/a-deeper-dive-into-the-rogers-ou...

Re:"Out of Band" network management is not trivial by immibis on Sunday July 07, 2024 @08:25AM (#40897131)
BTW: anyone who wants to really experience how complex internet routing is, go and join DN42 (https://dn42.dev). This is a fake internet built on a network of VPN tunnels and using the same routing systems. As long as you're just acting as a leaf node, it's pretty straightforward. If you want to attach to the network at multiple points and not just VPN them all to the same place, now you have to design a network just like an ISP would, with IGP and so on.
Re:"Out of Band" network management is not trivial by vitus on Sunday July 07, 2024 @10:04AM (#40897836)
Router config changes are simultaneously very commonplace and incredibly risky.

I've seen outages caused by a single bad router advertisement that caused global crashes due to route poisoning interacting with a vendor bug. RPKI enforcement caused massive congestion on transit links. Route leaks have DoSed entire countries (https://www.internetsociety.org/blog/2017/08/google-leaked-p...). Even something as simple as a peer removing rules for clearing ToS bits resulted in a month of 20+ engineers trying to figure out why an engineering director was sporadically being throttled to ~200kbps when trying to access Google properties.

Running a large-scale production network is hard.

edit: in case it is not obvious: I agree entirely with you -- the routine config changes that do risk the enterprise are often very hard to identify ahead of time.

Re:"Out of Band" network management is not trivial by Scoundreller on Sunday July 07, 2024 @02:31PM (#40899479)
the report stated: https://crtc.gc.ca/eng/publications/reports/xona2024.htm

> "this configuration change was the sixth phase of a seven-phase network upgrade process that had begun weeks earlier. Before this sixth phase configuration update, the previous configuration updates were completed successfully without any issue. Rogers had initially assessed the risk of this seven-phased process as “High.”

> However, as changes in prior phases were completed successfully, the risk assessment algorithm downgraded the risk level for the sixth phase of the configuration change to “Low” risk"

> Downgrading the risk assessment to “Low” for changing the Access Control List filter in a routing policy contravenes industry norms, which require high scrutiny for such configuration changes, including laboratory testing before deploying in the production network.

Overall, the lack of detail of the (regulator forced) post-mortem makes it impossible for the public to decide.

It's a Canadian telecom: They'll release detail when it makes them look good, and hide it if it makes them look bad.

Re:"Out of Band" network management is not trivial by throw0101d on Sunday July 07, 2024 @09:12PM (#40901838)
> Overall, the lack of detail of the (regulator forced) post-mortem makes it impossible for the public to decide.

Note: the publicly available post-mortem makes it difficult for the public to decide.

Per a news article:

> Xona Partners' findings were contained in the executive summary of the review report,[0] released this month. The CRTC says the full report contains sensitive information and will be released in redacted form at a later, unspecified, date.

* https://www.cbc.ca/news/politics/rogers-outage-human-error-s...

Re:"Out of Band" network management is not trivial by vitus on Monday July 08, 2024 @09:13AM (#40905127)
Certainly if it was downgraded only by the time it reached phase 6, then I would expect it to have gone through that higher scrutiny in earlier phases (including lab testing). My guess is that the existing lab testing was inadequate for surfacing issues that would only appear at production-scale.

If each of the six phases was a distinct set of config changes, then they really shouldn't have been bundled as part of the same network upgrade with the same risk assessment. But, charitably, I assumed that this was a progressive rollout in some form (my guess was different device roles, e.g. peering devices vs backbone routers). Should these device roles have been qualified separately via lab testing and more? Certainly. Were they? I have no idea.

Do I think there are systemic issues with how Rogers runs their network? Almost certainly. But from my perspective, the report (which was created by an external third-party) places too much blame on the downgrade of risk assessment as opposed to other underlying issues.

(As you can see, there is a lot of guesswork on my behalf, precisely because, as you mention, there isn't enough information in the executive summary to fill in these gaps.)

Re:"Out of Band" network management is not trivial by sidewndr46 on Sunday July 07, 2024 @10:00AM (#40897795)
It is likely no one at the C-Level knew the update had any risk
Re:"Out of Band" network management is not trivial by Scoundreller on Sunday July 07, 2024 @02:34PM (#40899500)
it was "high risk", and then downgraded to "low risk" as this several week and phase long project proceeded without initial issue.