mitchs

5 ms·

1.
by mitchs 3y ago
The most fun I've had with strace was debugging a 3-process deadlock. An snmp daemon was blocked waiting for a cli child process to finish, the cli was waiting for a response to a message on a socket it had open with a routing protocol
2.
by mitchs 3y ago
The doubling of J as a means of striding across the array also gives me some concern. While it is cache related, it is cache related for sneaky reasons. J is going to end up, in binary, with a ton of 0s at the end after being doubled over a
3.
by mitchs 4y ago
The important part is it safely allows you to pass references or other objects with lifetimes to those threads. (Or at least lets the compiler know so you can avoid having to write unsafe things yourself.) This happened to be useful for som
4.
by mitchs 4y ago
The big issue with v6 is you don't know what every ISP is doing with their IP space. The current RIPE recommendation is to delegate somewhere between a /48 to a /56 to every customer. Some ISPs might only delegate a 64, and p
5.
by mitchs 4y ago
Neat. I had made something similar for work a while back, but as a LD_PRELOAD library that intercepted calls to malloc and friends. It would add extra space to every allocation so it could add a pointer at the end that would point into a le
6.
by mitchs 4y ago
I don't like the idea of using caps lock frequently as a modifier. To me a frequently used modifier should either be on a thumb or on the opposite hand. I recently started trying to learn a one handed layout to give my injured right wr
7.
by mitchs 4y ago
I've been a fan of saying that things need to be compliant with RFC 1925 section 2.1. (It Has To Work.)
8.
by mitchs 4y ago
> "all observable behaviors of your system will be depended on by somebody" Ugh, a former team I was on had that to the extreme. We were customizing open source software for internal use. A lot of operators had (over years) dev
9.
by mitchs 5y ago
It depends on the context. Not every bgp speaker needs the full internet table and frequent route changes. If you use the network to balance traffic across servers, you just need a bgp speaker on a server to inject a few routes for the ip a
10.
by mitchs 5y ago
Eh, I think of the menu of options, taking out Starlink in Europe with a DDOS has a high probability of providing value for Russia and is safer to execute compared with the theoretical attack of getting locations out of a starlink ground st
11.
by mitchs 5y ago
IMO the motivated state wouldn't go through the trouble to attack sites physically when they could just DDOS spacex's public IPs. It isn't like their IP address blocks are a secret, and it wouldn't be that hard to narro
12.
by mitchs 5y ago
I'm curious, what everyone considers far enough in the future for your code. Eg. are you willing to write code that puts nanoseconds in a 64 but number? That is "only" 584 years after epoch. Would you consider that ok?
13.
by mitchs 5y ago
Anyone with typescript code that references the non-optional field will get type errors if it is made optional. Though stuffing the string with the v6 subnet wouldn't be the worst thing in the world. Any code that is blindly using it e
14.
by mitchs 5y ago
I wonder how long it will take for CDK to support this stuff. I'm not sure how they will back themselves out of the corner of subnets having a required ipv4 CIDR property.
15.
by mitchs 5y ago
All of this weird behavior is generally inet_aton. https://linux.die.net/man/3/inet_aton
16.
by mitchs 5y ago
BGP is spoken between networks. There are a lesser known "IGP" protocols stitching together the insides of those networks. IS-IS and OSPF being the most notable. Though the nature of the beast is that when you screw up BGP everyon
17.
by mitchs 5y ago
Or just cast the pointer to uint##_t and use be##toh and htobe## from <endian.h>? I think this is making a mountain out of a mole hill. I've spent tons of time doing wire (de)serialization in C for network protocols and endian sw
18.
by mitchs 5y ago
Refresh, as in transitioning from one image to another on the display. Partial refresh as in not running the waveform on pixels that don't change color, which dramatically reduces the visual noise for the user. The problem with partial
19.
by mitchs 5y ago
From what I've seen working on an e-reader, a big problem for any open source e ink product is the things EIH wants to keep secret about their displays. If you want to use the nice partial refresh waveform, the open source aspect of th
20.
by mitchs 6y ago
Heh, a popular consumer electronics product a room mate worked on shipped an update that used example.com as a connectivity test. Apparently they were on pace to rack up $20k/month in server costs. At least their user agent made it obv
21.
by mitchs 6y ago
I was initially troubled by the booting of Parler, but I've come around to seeing AWS's position as similar to the payment processors who don't want to deal with porn sites. Doing business with some clients creates risks. Tra
22.
by mitchs 6y ago
The real question who is using inet_aton(3). I'm betting none of the online converters.
23.
by mitchs 6y ago
They need to be capturing src/dest IPs as well as ports for AT&T to have any hope of using that data. Edit to make the comment more useful: If anyone is curious, look up "ECMP hashing." There are probably tons of parallel
24.
by mitchs 6y ago
Unfortunately TCP checksums are hot garbage given switch ASIC design. They are a 16 bit one's complement sum over a packet. If you get two bit flips in the same offset % 16, you can pass a checksum. The problem is routers slow down t
25.
by mitchs 6y ago
I was able to load up yocto's standard VMDKs into HyperV on my windows desktop, but AWS's import tool barfed on it. I build an embedded linux and wanted to use AWS as a hypervisor for larger scaled testing. (It was fairly easy to
26.
by mitchs 6y ago
Is the intent to get class E routed on the public internet, or just make it available in private networks? I've seen docker configs squatting on chunks of class E space for the local bridge interface, presumably because Linux takes it,
27.
by mitchs 6y ago
Something I see as wrong with C outside of the context of the Linux kernel is mostly something wrong with us the developers. We are far too content to live in filth. In addition to unsafe/irregular buffer handling, I also constantly se
28.
by mitchs 6y ago
For labbing with quagga you can get pretty far with Linux containers to emulate multiple routers on a single host. (I've used both lxc and docker to manage containers.) You can create virtual ethernet device pairs (ip link add veth0 ty
29.
by mitchs 6y ago
BGP operates as a rumor mill. Convergence is the process of all of the rumors settling into a steady state. The rumors are of the form "I can reach this range of IP addresses by going through this path of networks." Networks will
30.
by mitchs 6y ago
I've heard a fun story from the old timers in my org about a fiber outage in Brazil. A routine fiber cut occurred. They figure out how far from one end the cut is (there is gear that measures the time to see a light pulse reflect off o

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