Re: [GLLUG] IPv6 addresses
Hi, I think something associated with the ipv6 disussion and ISPs. Although they might give you ipv6 addresses, their dsl router probably provides no firewalling for it. I added my own firewall for ipv6. Kind regards James -- GLLUG mailing list GLLUG@mailman.lug.org.uk https://mailman.lug.org.uk/mailman/listinfo/gllug
Re: [GLLUG] Best NIX-based router/software for a small business network
On Mon, 14 Jun 2021 at 15:44, gvim via GLLUG wrote: > > With ransomeware becoming a threat to both small and large businesses I'm > inclined to advise small businesses to change their router as a first line of > defence. What is currently the best NIX-based router/software? pfSense? > The first and most important defense against Ransomware is not a firewall. The first thing to consider is how to recover after falling victim. If you can recover from a Ransomware attack without needing to pay ransom, you have defeated it. The main risk of a Ransomware attack is that they have managed to encrypt both your data and the backups of all the data. So, the best defense is using a backup system that cannot be attacked by a Ransomware attack. This is normally some sort to write once, store offsite backup, so the Ransomware attacker cannot delete or encrypt the backups. Once you have that protection, the next step is to look at ways to limit the disruption. This normally involves adding monitoring tools so that you are more likely to detect a malicious actor within your network. The final step is to try and prevent the attack in the first place. The problem with this final step is that there are always new zero day attacks, so whatever you come up with here is never 100% protection. That is another reason why the other steps above are more effective and more important to do . Kind Regards James Kind Regards James -- GLLUG mailing list GLLUG@mailman.lug.org.uk https://mailman.lug.org.uk/mailman/listinfo/gllug
Re: [GLLUG] Power control over IP
On Tue, 1 Jun 2021 at 15:55, stuart taylor via GLLUG wrote: > > hi all, > > We will have food for thouht at our admins meeting later this week. We have 4 > servers in our cabinet all quite old and all donated second hand: two IBM > X3250s (I think) and two SUN ultras. The solutions suggested are all very > good but probably beyond what I would be allowed to spend. Donations are > down, rent has stayed the same and the only good point is that staff are > allowed to work at home, so renting more space won't happen. > > Stuart > Hi Stuart, Those are very old servers indeed. It might be worth comparing rack rental costs vs using a VM on a service provider. The Surrey LUG server that I help maintain is a VM. Fortunately the VM is donated to us by the service provider, so it costs us nothing. But saying that, the resources it takes up are minimal so the service provider hardly notices it. I think it averages about 1 page hit per day! If you are a charity, it might be worth asking some service providers if they would donate a VM for your use also. I think the IBM X3250s have an option remote management card, that would do the same job as iDRAC, LOM. I don't know about the SUN ultras. Kind Regards James -- GLLUG mailing list GLLUG@mailman.lug.org.uk https://mailman.lug.org.uk/mailman/listinfo/gllug
Re: [GLLUG] Power control over IP
On Sat, 29 May 2021 at 16:38, Martin A. Brooks via GLLUG wrote: > > On 2021-05-29 16:19, stuart taylor via GLLUG wrote: > > Can anyone point me towards a suitable 'power > > supply over IP' solution? Are there any drawbacks to using these? > > Anything by APC. It's perfectly normal and reasonable to have remote > control power. > What servers do you have? Dell ones have iDRAC and HP ones have LOM (Lights out management) It allows access to power on/off the OS like you were pressing the power button, and also access to the console like VNC, but it allows you to see BIOS boot up messages also. So, what I am trying to say, is your server might already have the features you are asking for. You can also add PDUs and UPSs that are controllable over TCP/IP if you need them. Kind Regards James -- GLLUG mailing list GLLUG@mailman.lug.org.uk https://mailman.lug.org.uk/mailman/listinfo/gllug
Re: [GLLUG] SMS text scam warning
Hi, I received the classic post office scam sms message. I forwarded it to 7726, and to be fair, the web site was taken down fairly quickly. Kind Regards James On Sat, 24 Apr 2021 at 10:11, Chris Bell via GLLUG wrote: > > Hello, > bbc.co.uk/news/technology have relayed a warning from GCHQ about huge numbers > of messages sent to UK mobile phones claiming that there is a parcel on its > way, please download the "app" to get tracking details. It is nothing to do > with a parcel, the "app" is spyware aimed mainly at Android phones. > -- > Chris Bell > Website https://chrisbell.org.uk > > > > -- > GLLUG mailing list > GLLUG@mailman.lug.org.uk > https://mailman.lug.org.uk/mailman/listinfo/gllug -- GLLUG mailing list GLLUG@mailman.lug.org.uk https://mailman.lug.org.uk/mailman/listinfo/gllug
Re: [GLLUG] ssh local port forwarding remote interface binding.
On Thu, 14 Jan 2021 at 07:30, Tim Woodall via GLLUG wrote: > > Hi all, > > In > > ssh -N -L 8080:webserver:80 gateway > > Is there any way to specify which interface should be bound on gateway > other than by changing the routing table on gateway? > > Google isn't helping much as everything is talking about bind address > that the forwarded connection _listens_ on and I don't care about that, > Hi, Lets have: A = the client PC you are ssh from. B = gateway C = webserver. The above will open a port 8080 on A, listening on 127.0.0.1 When you connect to port 8080 on A, the session is tunnelled through the ssh port 22 session. B then opens a tcp session from B:anyport -> C:80 Does this help answer your question? Kind Regards James -- GLLUG mailing list GLLUG@mailman.lug.org.uk https://mailman.lug.org.uk/mailman/listinfo/gllug
Re: [GLLUG] IP address problems.
On Thu, 12 Nov 2020 at 12:26, John Winters via GLLUG < gllug@mailman.lug.org.uk> wrote: > On 12/11/2020 11:44, Chris Bell via GLLUG wrote: > [snip] > > My ISP Plusnet has failed to provide IPv6 as promised,... > > My recent experiences of Plusnet by way of people using them have all > been bad. Since the BT takeover they seem to be engaged in a determined > rush to the bottom. > > Just save yourself infinite amounts of grief and switch to Andrews and > Arnold. Chalk the unused bit of your existing contract up to > experience. (And I'm fairly certain you were given this advice many > years ago - why on earth are you still with Plusnet?) > > > I have heard great things about Andrews & Arnold, but have not personally used them. I am currently with Zen Internet. zen.co.uk. After joining them, they say you need to send them an email and IPv6 is then enabled. It worked, I am using IPv6 seamlessly with zen.co.uk. At least https://test-ipv6.com/ says so. Zen are reasonably priced and have responded to any support questions I had in a reasonable amount of time. Even to the point of them telling me that I would get exactly the same speeds on a cheaper tariff which I of course switched to. !!! If Plusnet promised IPv6, and are not delivering it, that is probably breach of contract, and you should be able to exit that contract without penalties and try an ISP that works. Kind Regards James -- GLLUG mailing list GLLUG@mailman.lug.org.uk https://mailman.lug.org.uk/mailman/listinfo/gllug
Re: [GLLUG] Moving from a Paradox database on Microsoft to Linux
On Tue, 28 Jul 2020 at 17:02, Chris Bell via GLLUG wrote: > > Hello, > I have been asked how best to transfer the data from a Paradox database to > something suitable on Linux. Any information welcome. Thanks. > -- While I have not used Paradox. I do have experience of transferring data from proprietary databases to more open ones. Steps I take: 1) Backup the existing database and create a VM or similar that can read it. This gives you a safe copy of the database and more importantly, the application that is used to access the database, in case months down the line you realise something is missing. 2) Note down as much about the database as possible. DB version. Driver versions etc. Depending on how old the database is, you might have a standard SQL interface to it. 3) Count the amount of rows in each table. 4) Do some test queries, and capture the output. Used later where you then do the same queries on the exported data to test compare that the data is identical. 5) Repeat (3) so that it covers all the tables. 6) Based on what you gather in (2) you have the following options: a) Use the original database's export features. (Quite often the best option) b) Use standard connectors, e.g. ODBC or JDBC to extract the data. c) Use a tool already written by someone to migrate the data. E.g. Paradox to Postgres or Paradox to mysql. Once you have the data in open source DBs such as postgres or mysql, it is then easily accessible and can be converted to other formats. 7) Points to note: DBs store fields in a large variety of character encodings. Rerun the queries you found in step 3 and 4 to ensure that you get all the same results on the exported data. DBs have field types, foreign keys, schemas. This metadata also needs exporting, and not only the records themselves. DBs also have "stored procedures" and various defined "views", different types of indexed fields. DBs behave differently. For example MS ACCESS definition of TRUE/FALSE in SQL query expressions is different from MYSQL's definition of TRUE/FALSE Exporting the DATA is one thing. Ensuring that the new application that you are using to access the DATA works the same as the old application is quite another matter and can be difficult to get right due to SQL differences between databases. Kind Regards James -- GLLUG mailing list GLLUG@mailman.lug.org.uk https://mailman.lug.org.uk/mailman/listinfo/gllug
Re: [GLLUG] Openssl and certificates
On Tue, 28 Jul 2020 at 09:48, Chris Bell via GLLUG wrote: > > Hello, > Openssl makes it easier to create my own CA and issue certificates for local > boxes with specified uses such as WWW and EMAIL, but I am not clear on the > best > approaches for multiple domains and boxes. I have dedicated individual boxes > to use as web server, email gateway, and email server, and multiple boxes for > each job to enable online backup and offline upgrades. Should individual > certificates be created for individual boxes or should the same certificate be > shared between all boxes allocated for each individual job? > Thanks for any information. > -- > Chris Bell > Website http://chrisbell.org.uk > Certificates for use with TLS have a number of possible options: 1) Host specific. So contain only one domain name. e.g. www.website.com 2) Multiple hosts sharing the certificate. Using something called "subject alternative names", you can have one cert, multiple domains. e.g. www.website.com, www.second.com, www.third.com all in a single cert. e.g. www.website.com, email-gw.website.com, email-srv.web all in a single cert. 3) Wildcard e.g. *.website.com So, the decision to have multiple certificates, or one wildcard certificate is really up to you. Either options are workable. If you use your own CA with openssl, it will work for you locally, but external users will not have the correct trusted root certificate so they will see warnings before connecting. Kind Regards James -- GLLUG mailing list GLLUG@mailman.lug.org.uk https://mailman.lug.org.uk/mailman/listinfo/gllug
Re: [GLLUG] Retrieving debian source package.
On Sun, 12 Jul 2020 at 10:14, Tim Woodall via GLLUG wrote: > > Hi All, > > I'm struggling to work out how to retrieve a debian source package. I > get this: > > tim@dirac:~/git/pkgrebuild/squid$ apt-get --print-uris -t buster source squid > Reading package lists... Done > E: Can not find version '4.6-1+deb10u2' of package 'squid' > E: Unable to find a source package for squid > It should just work. do you have the src entries in you /etc/apt/sources.list ? (or in sources.list.d) e.g. (This is the ubuntu equivalent, but the debian line should look similar) deb-src http://gb.archive.ubuntu.com/ubuntu/ bionic-updates main restricted -- GLLUG mailing list GLLUG@mailman.lug.org.uk https://mailman.lug.org.uk/mailman/listinfo/gllug
Re: [GLLUG] Webcam on Linux
On Thu, 18 Jun 2020 at 00:51, Andrew Black via GLLUG wrote: > > My laptop webcam has broken, and I dont have the energy to get it fixed under > RTB warranty. > Are there any gotchas about buying for linux (ubuntu 18.04). > > Ps > One site says Support multiple operating systems, including Windows, Mac OS, > Android Smart TV, etc. > I would like something a little more definitive than "etc". > Hi, USB webcams use a standard method for passing video and controls to the PC. To this end, pretty much every USB webcam should work with Linux. All the ones I have ever used just work with the same Linux driver that has been in the Linux kernel for years now. That includes: 1) webcam embedded in laptop. 2) webcam on usb cable that clips to the top of a display 3) Boroscopes / Endoscopes - (Really small cams that can fit in small places.) You mention "mic not important", but a mic based on a usb web cam is likely to be better quality than the mic in a laptop. mic's in laptops, tend to have quite a lot of background noise, mainly because they are designed badly. Of course, even better is a headset with an included mic. Kind Regards James -- GLLUG mailing list GLLUG@mailman.lug.org.uk https://mailman.lug.org.uk/mailman/listinfo/gllug
Re: [GLLUG] KVM Performance
On Fri, 12 Jun 2020 at 08:55, Tim Woodall via GLLUG wrote: > > On Tue, 9 Jun 2020, Ken Smith via GLLUG wrote: > > > Hi All, > > > > While in lockdown I decided to do some performance testing on KVM. I had > > believed that passing a block device through to a guest rather than using a > > QCOW2 file would get better performance. I wanted to see whether that was > > true and indeed whether using iSCSI storage was any better/worse. > > > > Interesting, I've been looking into this myself trying to improve > performance/reduce cpu usage. > Hi, My experience with KVM is that it is pretty good, performance wise, with block devices. E.g. qcow2 or actual block devices. KVM appears very slow for USB devices. Some of your tests appear to include USB in the path. USB devices are also very slow when used with WINE. (Running windows app on Linux) Kind Regards James -- GLLUG mailing list GLLUG@mailman.lug.org.uk https://mailman.lug.org.uk/mailman/listinfo/gllug
Re: [GLLUG] Systemd on Debian
On Sat, 23 May 2020, 09:07 Chris Bell via GLLUG, wrote: > On Friday, 22 May 2020 19:56:33 BST Andy Smith via GLLUG wrote: > > Thanks for the reply. Yes that is what I expected. I am trying to assign > IPv4 > and IPv6, with named local IP addresses to individual networks for local > access only, and global addresses for grouped networks, all with the > correct > prefix used for sending and receiving. This is slightly complicated > because I > also need to tunnel IPv6 in IPv4 until my ISP wakes up and provides the > IPv6 > promised several years ago, while making provision for it to appear at any > time. > > - > Hi, I am curious. Why do you think ipv6 link local address is useful for what you are trying to use it for? Ipv6 link local addresses are pretty useless things. Good for neighbour discovery, but not much else. Kind regards James -- GLLUG mailing list GLLUG@mailman.lug.org.uk https://mailman.lug.org.uk/mailman/listinfo/gllug
Re: [GLLUG] How worried should I be ...
On Fri, 22 May 2020 at 16:38, Alain D D Williams via GLLUG wrote: > > The message below was put to all login sessions this morning. I have never > seen > this before. There is nothing more in /var/log/messages. > > The machine is 8 years old, always switched on, AMD 8150 Eight-Core Processor. > > Should I take this as a warning and look to replace the machine or just shrug > my > shoulders & mutter something about cosmic rays ? > > TIA > > > Message from syslogd@mint at May 22 07:27:09 ... > kernel:[Hardware Error]: MC4 Error (node 0): L3 data cache ECC error. > > Message from syslogd@mint at May 22 07:27:09 ... > kernel:[Hardware Error]: Error Status: Corrected error, no action required. > If this is a one off, I would not worry about it. Bits flip occasionally. If you are getting it continuously, then power off the box. Reboot it, and see if the problem goes away. If it is always there, even after a cold power cycle, you have a hardware fault. -- GLLUG mailing list GLLUG@mailman.lug.org.uk https://mailman.lug.org.uk/mailman/listinfo/gllug
[GLLUG] [OT] How to look stupid on the international stage.
Hi, Would you hire this dev? https://www.zdnet.com/article/huawei-denies-involvement-in-buggy-linux-kernel-patch-proposal/ -- GLLUG mailing list GLLUG@mailman.lug.org.uk https://mailman.lug.org.uk/mailman/listinfo/gllug
Re: [GLLUG] Internet Data Rate
On Wed, 13 May 2020 at 16:14, Marco van Beek via GLLUG wrote: > > > > > ...MUST NOT (rfc2119) > > > > > I bet you know what BSI 0 is as well :-) > I once worked on a bid where the customer said we had to be 100% compliant to all the requirements. It was valued at about £10Million. So, I was working on the compliance statement, checking that our product and solution would be fully compliant and identifying what development work needed to be done, when I came across RFC 1149 on page 53 of the requirements. That RFC 1149 is surprising difficult to implement in software so we responded NC to it. Apparently, we were the only supplier that responded with a 99% compliance SOC. We won the bid. :-) -- GLLUG mailing list GLLUG@mailman.lug.org.uk https://mailman.lug.org.uk/mailman/listinfo/gllug
Re: [GLLUG] Link two RAIDs in one LVM?
Hi, I forgot another obvious question. Which filesystem are you using on the old 8TB disk? For example, if it is btrfs, you don't have to copy anything about. btrfs does its own raid 0. You can just add more disks as you need them and btrfs just uses them. Kind Regards James -- GLLUG mailing list GLLUG@mailman.lug.org.uk https://mailman.lug.org.uk/mailman/listinfo/gllug
Re: [GLLUG] Link two RAIDs in one LVM?
Hi, What size are the partitions on the old 8TB disks? Is it a single partition for all 8TB ? If you have a separate data from the OS partition: you could "rsync -avpP" the data/image/picture/whatever files over to the new disks on top of LVM. You could handle the OS partition offline. You can then do a final "catch up" rsync of the data in offline mode. Once everything is copied and you have unmounted the old disks, and have everything booting and running nicely on the new disks. You could then wipe the old disks, and redo them with LVM on them. I would allow at least a day or two for the first rsync of 8TB. Kind Regards James -- GLLUG mailing list GLLUG@mailman.lug.org.uk https://mailman.lug.org.uk/mailman/listinfo/gllug
Re: [GLLUG] Link two RAIDs in one LVM?
On Sat, 9 May 2020 at 12:03, Dr. Axel Stammler wrote: > > Hi, > > Thank you for your detailed look at possible setups. I remembered my old > setup incorrectly, though, so that I am not sure everything is applicable. My > original (2016) setup included two hard disk drives of not 4 TB but 8 TB > capacity in a RAID-1 that has reached 92 per cent capacity. > Ah, so the original disk drives are 8TB and not 4TB. So, going from: A: 8TB (current) B: 8TB (current) C: 8TB (new) D: 8TB (new) Some things to consider. 1) 8TB does not equal 8TB. Although the drives might say they are 8TB, the exact amount of sectors on the disk might differ between disk models. I would therefore chop the disk into 500GB partitions so that you can move them around at a later point if you wish. You RAID the 500GB partitions. You then put LVM (Logical Volume Management) on top, using LVM to join all the RAID 500GB volumes into a single LVM Volume group. You can then use LVM to expand/reduce filesystems as you need to. You did not say whether your existing disks used LVM or not. If not, build the new disks with LVM on top of RAID. (LVM on top of RAID is better than RAID on top of LVM) Extensibility: It would probably be a good time to think about extensibility in future. I.e What happens when you add more disks. The reasoning behind the RAID 500GB, is so you could migrate in 500GB chunks, were you to need to change the RAID method later, or such like. You can make the chunks even smaller if you wish, you just end up with more of them. It gives you a sort of tiled RAID. Solution: So, there is a solution that uses tiled RAID. LVM has a "mirror" option. https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/4/html/cluster_logical_volume_manager/mirrored_volumes If you used that, you would not need a RAID layer at all. You would create all the disks as a LVM volume group, and then create LVM partitions using the LVM mirror option. An LVM mirror divides the device being copied into regions that are typically 512KB in size, so a big improvement over the 500GB chunks suggestion above. This would also give flexibility, you could choose some of your data to be "mirror" and some not. LVM "mirror" also lets you migrate data while it is still mounted. You have the original LVM volume, mirror it onto a new disk, remove the original copy. So, I think moving to an "LVM mirror" solution is your best bet for future extensibility. There are also other options like RAID 5 and RAID 6, but they have the associated "extensibility" problems. Kind Regards James -- GLLUG mailing list GLLUG@mailman.lug.org.uk https://mailman.lug.org.uk/mailman/listinfo/gllug
Re: [GLLUG] Link two RAIDs in one LVM?
Hi, Regarding which are SMR. Here is a good place to start: https://hardware.slashdot.org/story/20/04/29/2119250/toshiba-publishes-full-list-of-its-drives-using-slower-smr-technology TOSHIBA: https://toshiba.semicon-storage.com/ap-en/company/news/news-topics/2020/04/storage-20200428-1.html WD: https://www.tomshardware.com/news/wd-lists-all-drives-slower-smr-techNOLOGY Seagate: https://blocksandfiles.com/2020/04/15/seagate-2-4-and-8tb-barracuda-and-desktop-hdd-smr/ It seems that drive manufactures were being a bit secretive about it, but they have all come clean now, documenting which HDD are SMR. Kind Regards James On Sat, 2 May 2020 at 16:57, Dr. Axel Stammler via GLLUG wrote: > > Hi, > > On Tue 2020-04-28 16.10.42, Greater London Linux User Group wrote: > > >Next up, if your drives don't support SCTERC timeout facility then > >this is not ideal for a Linux RAID system but can be worked around > > Thanks. This is another great tip. Is there any way to find out if a drive > has that problem before buying it? > > Cheers, > > Axel > -- > GLLUG mailing list > GLLUG@mailman.lug.org.uk > https://mailman.lug.org.uk/mailman/listinfo/gllug -- GLLUG mailing list GLLUG@mailman.lug.org.uk https://mailman.lug.org.uk/mailman/listinfo/gllug
Re: [GLLUG] Link two RAIDs in one LVM?
On Tue, 28 Apr 2020 at 12:18, Dr. Axel Stammler via GLLUG wrote: > > Hi, > > I have a 4 TB RAID system (two identical hard disks combined in a RAID-1, > created using mdadm). Now, after a few years, this has reached 90% capacity, > and I am thinking about first adding another similar 8 TB RAID system and > then combining them into one 12 GB RAID 1+0 filesystem. I should be grateful > for any tips, especially about buying two 8 TB harddisks. > > Which hardware parameters should I look at? > > Which method should I use to combine both RAID systems into one? > > - linear RAID > - RAID-0 > - Large Volume Management (using pvcreate, vgcreate, lvcreate) > Hi, First for RAID, avoid SMR HDDs. (Shingled magnetic recording) I would probably RAID 5 them. 4+4 = 8 for the first disk, against the two other 8 disks. So, say disks are A(4TB), B(4TB), C(8TB), D(8TB) Partitions the 8TB in half. A(4TB), B(4TB), C1(4TB), C2(4TB), D1(4TB), D2(4TB) RAID 5: A,C1,D1 RAID 5: B,C2,D2 Then put the two RAID arrays in the same LVM VG, so that they look like one big disk for the OS. Another alternative is using XFS or BTRFS and configure them with replicas. That is where the filesystem does the replication, thus not needing RAID at all. Or, you could take the approach I take. I remove the old 4TB disks and only copy the few files I need on to the 8TB disks going forward. I can always plug the old 4TB disks in if I need an old file. I have written my own indexer for this. It scans the whole disk, creating an index and thumbnails and then only store the index and thumbnails on the 8TB disks. The index is stored in Elastic Search, so makes it easy to find the files again, and also which disk they are on. So, files I hardly ever need are stored on powered off disks. Kind Regards James -- GLLUG mailing list GLLUG@mailman.lug.org.uk https://mailman.lug.org.uk/mailman/listinfo/gllug
Re: [GLLUG] Perl programming project
On Thu, 20 Feb 2020 at 10:57, Marco van Beek via GLLUG wrote: > Basically we currently have an LDAP address book which is used by our > desktop phones and our scanner. We also have started to use CardDAV as > support is slowly extended into Thunderbird and Outlook (via a plug-in) > but the VOIP phones and MFD do not understand CardDAV, so we need > something to allow CardDAV to answer LDAP queries. After much > unsuccessful searching (found one bit of bespoke code but the author > never got back to me) I have figured out that OpenLDAP can use a Perl > backend, and there is a Perl module that does CardDAV. We do not need a > full two way conversation between the two, but as a project this does > have the potential for a much bigger scope. It seems a bit confused to me. Do you have an LDAP server or a CardDAV server or both? I would have thought having a single server that can handle both query types is the way to go, because I expect the data model behind CardDAV and LDAP is different. One would probably need to design the data model from the start with both protocols in mind, to get this working well. KInd Regards James -- GLLUG mailing list GLLUG@mailman.lug.org.uk https://mailman.lug.org.uk/mailman/listinfo/gllug
Re: [GLLUG] radvd leaking memory
On Tue, 4 Feb 2020 at 17:29, Tim Woodall via GLLUG wrote: > > Hi, > > Last night radvd got killed by the oom killer > Feb 4 02:32:11 firewall17 vmunix: [1762825.239631] [ pid ] uid tgid > total_vm rss pgtables_bytes swapents oom_score_adj name > Feb 4 02:32:11 firewall17 vmunix: [1762825.239671] [ 3882] 105 3882 > 6849019387 58163248648 0 radvd > > When I look on another host I see that it's rather larger than I would > have expected: > 3247 radvd 20 0 177228 41016556 S 0.0 24.0 16:07.26 radvd > > After a bounce it looks better: > 1030 radvd 20 02444 1616 1476 S 0.0 0.9 0:00.01 radvd > > > I cannot find anything about radvd having memory leaks. Does anyone know > if this large memory footprint is expected (I'm running it on a VM with > not much memory and I can increase that if necessary)? > > I can obviously restart it to avoid this issue. I wonder if it could be > related to VPN interfaces that are constantly being created and removed. > Well its open source, so in theory you could diagnose the leak yourself. clang has a very useful "-fsanitize=address" option. It allows the program to run pretty much at full speed, and then reports memory leaks. -- GLLUG mailing list GLLUG@mailman.lug.org.uk https://mailman.lug.org.uk/mailman/listinfo/gllug
Re: [GLLUG] Downside of FTTP
On Wed, 4 Dec 2019, 15:50 Chris Bell via GLLUG, wrote: > Hello, > Someone has posted a message on a local forum that his Redcare link to ADT > was > cut without any warning from BT when he was re-connected by FTTP. > ADT have offered an upgrade for £1,711. > -- Hi, Do you have a link to the forum? A quick google of "Redcare link to ADT", says it is a GSM link, so should not even touch the FTTP. I don't have Redcare or FTTP, as I use alternatives, so I don't really know how Redcare connects. Kind Regards James -- GLLUG mailing list GLLUG@mailman.lug.org.uk https://mailman.lug.org.uk/mailman/listinfo/gllug
Re: [GLLUG] Advice about my Freeance work
> > Another vote for AAISP. As well as static ip, they support reverse dns > which is almost essential if you want to send mail. They give a full /48 > for ipv6. While knowing ipv6 probably won't win you any clients now, > maybe in 5-10 years being able to step in and solve a problem that the > ipv4 only people don't understand might be important. > I use Zen Internet, and they have been good also. IPv4, IPv6, reverse dns etc. -- GLLUG mailing list GLLUG@mailman.lug.org.uk https://mailman.lug.org.uk/mailman/listinfo/gllug
Re: [GLLUG] Multiple grub installs in xen guest
On Fri, 11 Oct 2019 at 14:28, Tim Woodall via GLLUG wrote: > > Does anyone know whether the default debian grub-xen stuff allows you to > select the grub root? > > I have a bootable xen image that uses grub from /dev/xvda2. I also have > one that uses grub from /dev/vg-mirror/boot. (the vg is inside the disk > I export to the guest, not the vg of dom0) > > I want to be able to boot the former, but have the latter available to > mount. But it is insistent that it will use the vg boot in favour of the > raw ext3 one. > I have not used xen in a long time so cannot help there. From my experience with grub, sometimes you have to manually configure what the possible boot devices are. But, have you considered Linux's own VM tech, using KVM and QEMU ? It has a nice option of loading the kernel before starting the VM, thus bypassing the need for grub entirely. virt-manager is an OK GUI to get going with it. There are also various web based tools to manage the VMs also. I have been playing with an AMD Vega GPU passthru on it recently, and fixed a QEMU bug on the way. AMD developers are very easy to get hold of when needed. Works very nicely, and stably now. Kind Regards James -- GLLUG mailing list GLLUG@mailman.lug.org.uk https://mailman.lug.org.uk/mailman/listinfo/gllug
Re: [GLLUG] Server in London
Bitfolk +1 from me. Great customer service also. I help admin a server hosted by bitfolk. James On Fri, 11 Oct 2019, 11:50 Alan Pope via GLLUG, wrote: > Hi Dr Alex, > > On Fri, 11 Oct 2019 at 10:22, Dr. Axel Stammler via GLLUG < > gllug@mailman.lug.org.uk> wrote: > >> Thank you very much for making me aware of all those options. I have >> started looking into several of them, which may obviously take a minute or >> two. OTOH, I feel rather disinclined to work with any but the smallest >> companies as large companies bring their own agenda which is usually quite >> different from mine. >> >> > I don't think I'm maligning them by saying this, but Bitfolk certainly > falls into the "smallest companies" bracket. Also, another +1 from me as a > long-term (~12 years) happy customer. > > >> I have once tried a virtual server, with some extremely pleasant and some >> not so pleasant results. If the GLLUG has a meeting at the beginning of >> next week, it might be best to just have a chat there. >> > > I have had no problems with bitfolk which weren't my own incompetence or a > system wide issue that was resolved and detailed fully by Andy. > > Cheers, > Al. > -- > GLLUG mailing list > GLLUG@mailman.lug.org.uk > https://mailman.lug.org.uk/mailman/listinfo/gllug -- GLLUG mailing list GLLUG@mailman.lug.org.uk https://mailman.lug.org.uk/mailman/listinfo/gllug
Re: [GLLUG] Server in London
On Thu, 10 Oct 2019 at 20:59, Dr. Axel Stammler via GLLUG wrote: > > Hello, David, > > Thanks for your quick reply. My internet connection is slow and unreliable, > and my power supply has (on rare occasions) failed, too. Part of the server > would be devoted to database replication. I don't want to work with any cloud > systems offered by big companies. > > And, in a pinch I could ask for the server to be handed to me. > > Regards > > Axel > What size is the data/database/files you wish store online ? Some idea as to how busy it might be? If I understand it correctly, you have some data that you wish to access when not at home. Your home internet is slow and un-reliable, so you would like to put is somewhere that has more reliable internet links. Is the data private or public for everyone to view? Kind Regards James -- GLLUG mailing list GLLUG@mailman.lug.org.uk https://mailman.lug.org.uk/mailman/listinfo/gllug
Re: [GLLUG] Reading USB serial port broken
On Fri, 20 Sep 2019 at 08:02, Henrik Morsing via GLLUG wrote: > > > Hi, > > I have an Arduino connected via USB to a PC, to read sensors around my house. > It calls a Python script as a Munin plugin. > > For quite some time now, and I think this possible broke after an upgrade, > the Python script gets no output from ttyACM0. > > Unless I run a 'tail -f' on the device from the command line! Then it works. > Otherwise the script just times out getting nothing. > > I'm guessing it's down to a kernel change in how it opens or signals through > USB serial devices but what? Googling for a year has found nothing similar to > this problem. I'm not really an expert on serial devices and even less on USB > serial devices. > > It's getting really frustrating now as the monitoring just never works > anymore, so any help appreciated. > Serial programming is notoriously complicated. I have done it in python before, doing a similar thing that you are doing. Would you be able to post the python script so we can see how you are setting up the tty and how you read/write bytes to it? It is very messing writing python code that catches all possible errors. For example, I was seeing RF noise coming from all the sensors, occasionally knocking the USB link off/on. My python code then had to detect this, close the tty, wait a mo for it to settle, then open it again. After that, in the end I dumped Python, and used a mixture of Java, C and C++. Essentially moving from domogik (Python) to openhab (mainly Java but with C, C++ for low level device/tty access.) Kind Regards James -- GLLUG mailing list GLLUG@mailman.lug.org.uk https://mailman.lug.org.uk/mailman/listinfo/gllug
