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Re: Reminder: November WLUG Meeting at the Hudson Public Library! Topic: Intel Management Engine.

by Forrest S

Hey Tim, Names Forrest I introduced myself a while back on the forum I live in Hudson and know the area pretty well so I will be there for my first in-person meeting and so for everyone who does not know there is a parking lot in the back behind the fire station it is right next to the library

Nov. 18, 2021

Reminder: November WLUG Meeting at the Hudson Public Library! Topic: Intel Management Engine.

by Tim Keller

Hey Everybody, We've got a meeting this Thursday November 18th, 2021 at 7pm - 8:30pm at the Hudson Public Library! Firstly, a big shout out to Joshua Stone for making the reservation at the Hudson Public Library. Secondly, the meeting will also be online at our usual Jitsi location for people who can't make it in person. https://meet.jit.si/WlugMA The topic we'll be discussing at the meeting is the Intel Management Engine technology buried in every Intel CPU. This technology includes a version of Minix running on a separate core inside your CPU you don't control. Moreover, with the right software, changes to your machine can be made remotely, even when the system is powered off (but connected to power). As with all this stuff, of course since the whole thing is cooked into the firmware, it's full of security flaws, etc.. We'll talk about those flaws and how to disable it! We'll also likely touch on the Tesla Dojo D1 processing unit. They've made some claims that I've posted to the mailing list. Logan did some digging and it turns out their claims are not as blow your mind as would be first interpreted. The Hudson Public Library does allow food and drink, so I will bring the usual pretzels and snacks. Afterwards we will be going to Rail Trail Flatbread <https://railtrailflatbread.com/>for dinner. Toss me a line privately if you'll be attending so we've got an idea of how many people will be going out for dinner. I look forward to seeing you there! Later, Tim. -- I am leery of the allegiances of any politician who refers to their constituents as "consumers".

Nov. 16, 2021

Re: Dojo D1

by Tim Keller

That's good to know.. Thanks for digging deeper into this. On Mon, Nov 15, 2021 at 4:48 PM Logan Brown via WLUG <wlug(a)lists.wlug.org> wrote: > So, as with everything Tesla, there’s a whole lot of asterisks involved: > > - Each individual Dojo D1 chip is only 22.6 TFLOP FP32 at 400w of > power consumption. Compared to the newly announced AMD Instinct MI250, > which pushes 45.3 TFLOP F32 at 500w. > - The claims of 9 PFLOP per tile is only if you’re using the new > custom floating point format that they’ve created ( > https://www.scribd.com/document/535276674/Tesla-Dojo-Technology) > Regular FP32, you’re talking about 565 TFLOP per tile or 6.7 PFLOP per rack > (120kw draw) - fast, but when AMD is offering 348 TFLOP F32 in a standard > 2U form factor and you can put 24 of those in a standard rack for 8.3 PFLOP > per rack (96kw draw), not so impressive. > > > > > > > > *From: *Bob via WLUG <wlug(a)lists.wlug.org> > *Sent: *Monday, November 15, 2021 16:29 > *To: *Tim Keller via WLUG <wlug(a)lists.wlug.org> > *Cc: *Bob <robert.athol.mass(a)gmail.com> > *Subject: *[WLUG] Re: Dojo D1 > > > > I want two. > > On 9/29/2021 4:37 PM, Tim Keller via WLUG wrote: > > I just finally got to see the stuff about Tesla's Dojo Processor stuff. > > > > 9 PFLOPS per "tile" and 36 TB/s of bandwidth. > > https://www.youtube.com/watch?v=pPHX7e1BxSM > > Um..wow. > > > > Tim. > > > > -- > > I am leery of the allegiances of any politician who refers to their > constituents as "consumers". > > > > _______________________________________________ > > WLUG mailing list -- wlug(a)lists.wlug.org > > To unsubscribe send an email to wlug-leave(a)lists.wlug.org > > Create Account: https://wlug.mailman3.com/accounts/signup/ > > Change Settings: https://wlug.mailman3.com/postorius/lists/wlug.lists.wlug.org/ > > Web Forum/Archive: https://wlug.mailman3.com/hyperkitty/list/wlug@lists.wlug.org/message/OOBBL… > > > _______________________________________________ > WLUG mailing list -- wlug(a)lists.wlug.org > To unsubscribe send an email to wlug-leave(a)lists.wlug.org > Create Account: https://wlug.mailman3.com/accounts/signup/ > Change Settings: > https://wlug.mailman3.com/postorius/lists/wlug.lists.wlug.org/ > Web Forum/Archive: > https://wlug.mailman3.com/hyperkitty/list/wlug@lists.wlug.org/message/FRZFO… > -- I am leery of the allegiances of any politician who refers to their constituents as "consumers".

Nov. 16, 2021

Re: Dojo D1

by Logan Brown

So, as with everything Tesla, there’s a whole lot of asterisks involved: * Each individual Dojo D1 chip is only 22.6 TFLOP FP32 at 400w of power consumption. Compared to the newly announced AMD Instinct MI250, which pushes 45.3 TFLOP F32 at 500w. * The claims of 9 PFLOP per tile is only if you’re using the new custom floating point format that they’ve created (https://www.scribd.com/document/535276674/Tesla-Dojo-Technology) Regular FP32, you’re talking about 565 TFLOP per tile or 6.7 PFLOP per rack (120kw draw) - fast, but when AMD is offering 348 TFLOP F32 in a standard 2U form factor and you can put 24 of those in a standard rack for 8.3 PFLOP per rack (96kw draw), not so impressive. From: Bob via WLUG<mailto:wlug@lists.wlug.org> Sent: Monday, November 15, 2021 16:29 To: Tim Keller via WLUG<mailto:wlug@lists.wlug.org> Cc: Bob<mailto:robert.athol.mass@gmail.com> Subject: [WLUG] Re: Dojo D1 I want two. On 9/29/2021 4:37 PM, Tim Keller via WLUG wrote: I just finally got to see the stuff about Tesla's Dojo Processor stuff. 9 PFLOPS per "tile" and 36 TB/s of bandwidth. https://www.youtube.com/watch?v=pPHX7e1BxSM Um..wow. Tim. -- I am leery of the allegiances of any politician who refers to their constituents as "consumers". _______________________________________________ WLUG mailing list -- wlug(a)lists.wlug.org<mailto:wlug@lists.wlug.org> To unsubscribe send an email to wlug-leave(a)lists.wlug.org<mailto:wlug-leave@lists.wlug.org> Create Account: https://wlug.mailman3.com/accounts/signup/ Change Settings: https://wlug.mailman3.com/postorius/lists/wlug.lists.wlug.org/ Web Forum/Archive: https://wlug.mailman3.com/hyperkitty/list/wlug@lists.wlug.org/message/OOBBL…

Nov. 15, 2021

Re: Use same hostname internally and externally

by Brandon Hartshorn

On 2021-11-12 10:50, brad via WLUG wrote: > However android and iOS do not appear to honer my local dns server — > I’m not sure why — so they resolve the address to a routable IP and > connect from within the private 192.168.1.0 subnet. My firewall sees > this and drops it b/c it is a non-routable IP address connecting to > the external interface. (I got this info by running tcpdump and > watching traffic). > > Has anyone attempted something similar? Is there something I’m > overlooking? (Probably) Yeah, you're not missing anything - mobile devices are just sortof a PITA. Throw in a work device which tunnels all DNS over VPN and it turns in to a real headache. If you can't seem to get the phones to obey (blocking external DNS or re-directing it *might* work), you may have to resort to NAT reflection. It's working OK for me on pfSense. Unfortunately, all traffic ends up going through the firewall, but the performance hit probably isn't too critical for most things. Here's docs for doing this in pfSense, other "real" routers should have a similar functionality: https://docs.netgate.com/pfsense/en/latest/nat/reflection.html

Nov. 15, 2021

Meeting in Hudson and Main Street Contest

by Joshua Stone

Hey all, I'm posting to confirm that the venue for our upcoming in-person meeting at 7PM will be held at the Hudson Public Library! We may also want to look into eating options after the meeting, many of which are on Main Street: https://www.discoverhudson.org/taste/ My vote goes to the Rail Trail Flatbread which is close to the library and has some incredibly tasty menu items! And speaking of main streets, I'm happy to announce that Hudson has become a semi-finalist for the Main Street Contest! https://mainstreetcontest.com https://mainstreetcontest.com/profile/102 I think it's awesome that the town has seen so much growth since we moved here and gives us a sense of community. I'm excited to see where it'll go! - Josh

Nov. 15, 2021

Re: Use same hostname internally and externally

by John Stoffel

>>>>> "brad" == brad <bkn(a)ithryn.net> writes: brad> On Nov 12, 2021, at 19:34, John Stoffel <john(a)stoffel.org> wrote: brad> "brad" == brad via WLUG <wlug(a)lists.wlug.org> writes: brad> To quickly summarize my problem/question, I’d like to host a brad> nextcloud server at my house and be able to access it with the brad> same hostname whether I’m home or away. brad> I own a domain, let’s call it example.com. Its main DNS record brad> points to a node at digital oceans. However I’d like to host a brad> sub-domain at my house, let’s call it brad> home.example.com. Currently home.example.com resolves to a brad> routable IP address at my house. brad> - When I’m on the road, I’d like to be able to connect to https://home.example.come brad> - When I’m home, I’d like to be able to connect to https://home.example.com. brad> The above works on a well-behaved desktop receiving dns servers brad> via dhcp. Specifically, I have setup local dns to resolve brad> home.example.com to 192.168.1.1. Searching this topic has taught brad> me that this method is called Split-DNS. brad> However android and iOS do not appear to honer my local dns brad> server — I’m not sure why — so they resolve the address to a brad> routable IP and connect from within the private 192.168.1.0 brad> subnet. My firewall sees this and drops it b/c it is a brad> non-routable IP address connecting to the external interface. (I brad> got this info by running tcpdump and watching traffic). brad> Are your iphone and android getting their data from the Wifi network brad> or their phone network? brad> This is a great question and led to what I believe is the solution. brad> You might need to sniff port 53 traffic on brad> your firewall and see where they're sending queries to. Then you brad> might need to block or redirect those queries to your own internal DNS brad> server. brad> I did sniff port 53 (and 853) to observe dns traffic. I also brad> sniffed port 67 and 68 to make sure that the DNS server was brad> getting sent w/ the dhcp request. All was good on the dhcp brad> front, and port 53 sniffing did display the fact that my brad> internal domain names were getting resolved to CNAMEs, but on brad> Andoird, it stopped at that step. I.e. android got a CNAME for brad> up.internal.example.com, but did not resolve the CNAME any brad> further. Interesting, I'm kinda surprised. brad> Has anyone attempted something similar? Is there something I’m brad> overlooking? (Probably) You might need/want to reboot the Android, or see if there's a way to flush it's own internal DNS cache. But I don't have any android to play with at home. brad> I've been meaning to do it myself, putting in a local internal brad> override for my dynamic DNS external name, so I can conncent from both brad> inside and outside (when I'm on the $WORK VPN mostly) without having brad> to remember things. Silly to bounce SSH across the country to get brad> downstairs... but when you sit at a $WORK laptop most days... it's brad> nice to be able to hit home stuff via SSH and screen. brad> Agreed, I recently setup wireguard to use as VPN for this brad> purpose. I just ssh home, no really need for wireguard at this time. brad> My goal is to not do special configurations on enduser devices. A laudable goal for sure! brad> What is your firewall or router at home? Depending on what you have, brad> you might be able to block outgoing port 53 traffic, or redirect it to brad> your internal DNS server so those devices get the results you want. brad> I use OpnSense at home, so if that's what you're using, we can work brad> together on this. brad> My firewall is openbsd — my preferred firewall OS as I love pf — brad> and my name server is unbound. I believe OpnSense is built on a brad> BSD, so unbound maybe an option for you. I'm already running unbound as my internal DNS server. brad> On to the solution, or at least ‘what works for me’. As far as I brad> can tell unbound is not an authoritative name server, so I had brad> to change all the CNAMEs to A records. That is a little annoying brad> when I comes to my config file, but it does work. No, unbound works just fine as an authoritative nameserver from what I know. It's dnsmasq which doesn't work as an authoritative. I think the solution of using A records is actually the right one, since you want to override the outside world's A record for your hostname, so using a CNAME inside isn't going to really help because it will lookup the name, and I *think* A records are a higher priority than CNAMEs in the response. So just doing a CNAME won't do the trick. Since it's not something that changes often, having to buidl your own A record shouldn't be that big a deal. brad> For your reference, a related bug report for opnsense is linked brad> below with subsequent links about why unbound and CNAMEs do not brad> go together. brad> https://github.com/opnsense/core/issues/1041 This is an old bug, I'm running the latest production release of OpnSense and unbound, so I think I'm ok. brad> Thanks for provoking my curiosity into the eventual solution! Excellent! John

Nov. 13, 2021

Re: Use same hostname internally and externally

by brad

> On Nov 12, 2021, at 19:34, John Stoffel <john(a)stoffel.org> wrote: > >>>>>> "brad" == brad via WLUG <wlug(a)lists.wlug.org> writes: > > brad> To quickly summarize my problem/question, I’d like to host a > brad> nextcloud server at my house and be able to access it with the > brad> same hostname whether I’m home or away. > > brad> I own a domain, let’s call it example.com. Its main DNS record > brad> points to a node at digital oceans. However I’d like to host a > brad> sub-domain at my house, let’s call it > brad> home.example.com. Currently home.example.com resolves to a > brad> routable IP address at my house. > > brad> - When I’m on the road, I’d like to be able to connect to https://home.example.come > brad> - When I’m home, I’d like to be able to connect to https://home.example.com. > > brad> The above works on a well-behaved desktop receiving dns servers > brad> via dhcp. Specifically, I have setup local dns to resolve > brad> home.example.com to 192.168.1.1. Searching this topic has taught > brad> me that this method is called Split-DNS. > > brad> However android and iOS do not appear to honer my local dns > brad> server — I’m not sure why — so they resolve the address to a > brad> routable IP and connect from within the private 192.168.1.0 > brad> subnet. My firewall sees this and drops it b/c it is a > brad> non-routable IP address connecting to the external interface. (I > brad> got this info by running tcpdump and watching traffic). > > Are your iphone and android getting their data from the Wifi network > or their phone network? This is a great question and led to what I believe is the solution. > You might need to sniff port 53 traffic on > your firewall and see where they're sending queries to. Then you > might need to block or redirect those queries to your own internal DNS > server. > I did sniff port 53 (and 853) to observe dns traffic. I also sniffed port 67 and 68 to make sure that the DNS server was getting sent w/ the dhcp request. All was good on the dhcp front, and port 53 sniffing did display the fact that my internal domain names were getting resolved to CNAMEs, but on Andoird, it stopped at that step. I.e. android got a CNAME for up.internal.example.com, but did not resolve the CNAME any further. > brad> Has anyone attempted something similar? Is there something I’m > brad> overlooking? (Probably) > > I've been meaning to do it myself, putting in a local internal > override for my dynamic DNS external name, so I can conncent from both > inside and outside (when I'm on the $WORK VPN mostly) without having > to remember things. Silly to bounce SSH across the country to get > downstairs... but when you sit at a $WORK laptop most days... it's > nice to be able to hit home stuff via SSH and screen. > Agreed, I recently setup wireguard to use as VPN for this purpose. > brad> My goal is to not do special configurations on enduser devices. > > What is your firewall or router at home? Depending on what you have, > you might be able to block outgoing port 53 traffic, or redirect it to > your internal DNS server so those devices get the results you want. > > I use OpnSense at home, so if that's what you're using, we can work > together on this. > My firewall is openbsd — my preferred firewall OS as I love pf — and my name server is unbound. I believe OpnSense is built on a BSD, so unbound maybe an option for you. On to the solution, or at least ‘what works for me’. As far as I can tell unbound is not an authoritative name server, so I had to change all the CNAMEs to A records. That is a little annoying when I comes to my config file, but it does work. For your reference, a related bug report for opnsense is linked below with subsequent links about why unbound and CNAMEs do not go together. https://github.com/opnsense/core/issues/1041 Thanks for provoking my curiosity into the eventual solution! — brad

Nov. 13, 2021

Re: Use same hostname internally and externally

by John Stoffel

>>>>> "brad" == brad via WLUG <wlug(a)lists.wlug.org> writes: brad> To quickly summarize my problem/question, I’d like to host a brad> nextcloud server at my house and be able to access it with the brad> same hostname whether I’m home or away. brad> I own a domain, let’s call it example.com. Its main DNS record brad> points to a node at digital oceans. However I’d like to host a brad> sub-domain at my house, let’s call it brad> home.example.com. Currently home.example.com resolves to a brad> routable IP address at my house. brad> - When I’m on the road, I’d like to be able to connect to https://home.example.come brad> - When I’m home, I’d like to be able to connect to https://home.example.com. brad> The above works on a well-behaved desktop receiving dns servers brad> via dhcp. Specifically, I have setup local dns to resolve brad> home.example.com to 192.168.1.1. Searching this topic has taught brad> me that this method is called Split-DNS. brad> However android and iOS do not appear to honer my local dns brad> server — I’m not sure why — so they resolve the address to a brad> routable IP and connect from within the private 192.168.1.0 brad> subnet. My firewall sees this and drops it b/c it is a brad> non-routable IP address connecting to the external interface. (I brad> got this info by running tcpdump and watching traffic). Are your iphone and android getting their data from the Wifi network or their phone network? You might need to sniff port 53 traffic on your firewall and see where they're sending queries to. Then you might need to block or redirect those queries to your own internal DNS server. brad> Has anyone attempted something similar? Is there something I’m brad> overlooking? (Probably) I've been meaning to do it myself, putting in a local internal override for my dynamic DNS external name, so I can conncent from both inside and outside (when I'm on the $WORK VPN mostly) without having to remember things. Silly to bounce SSH across the country to get downstairs... but when you sit at a $WORK laptop most days... it's nice to be able to hit home stuff via SSH and screen. brad> My goal is to not do special configurations on enduser devices. What is your firewall or router at home? Depending on what you have, you might be able to block outgoing port 53 traffic, or redirect it to your internal DNS server so those devices get the results you want. I use OpnSense at home, so if that's what you're using, we can work together on this. John

Nov. 13, 2021

Use same hostname internally and externally

by brad

All, To quickly summarize my problem/question, I’d like to host a nextcloud server at my house and be able to access it with the same hostname whether I’m home or away. I own a domain, let’s call it example.com. Its main DNS record points to a node at digital oceans. However I’d like to host a sub-domain at my house, let’s call it home.example.com. Currently home.example.com resolves to a routable IP address at my house. - When I’m on the road, I’d like to be able to connect to https://home.example.come - When I’m home, I’d like to be able to connect to https://home.example.com. The above works on a well-behaved desktop receiving dns servers via dhcp. Specifically, I have setup local dns to resolve home.example.com to 192.168.1.1. Searching this topic has taught me that this method is called Split-DNS. However android and iOS do not appear to honer my local dns server — I’m not sure why — so they resolve the address to a routable IP and connect from within the private 192.168.1.0 subnet. My firewall sees this and drops it b/c it is a non-routable IP address connecting to the external interface. (I got this info by running tcpdump and watching traffic). Has anyone attempted something similar? Is there something I’m overlooking? (Probably) My goal is to not do special configurations on enduser devices. Thanks, — brad

Nov. 12, 2021