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Is there any point in using an 'unusual' private IP address range for security?
by Chris Green 18 May '14

18 May '14

I am in the process of reconfiguring my home LAN. Currently my desktop computer (which is also an 'always on' server machine) is visible to the outside world on several ports: ssh, smtp, http and maybe a couple of others (I'd have to check the router configuration to be sure). I have two ADSL connections, both with static IP and I use a Draytek Vigor 2820n router for load balancing. The 2820n handles one ADSL connection and there's an old Speedtouch ADSL modem/router on the other phone line whose LAN side connects to the 2820n's ethernet WAN input. What I'm thinking of doing to improve my security (or at least reduce the likelihood of a break-in doing much damage) is to have a dedicated 'dmz' server on the LAN/WAN between the Speedtouch router and the 2820n's WAN port. I can then open up the appropriate ports on *that* system to provide access from the outside world but if someone breaks in they won't be able to see anything much except that machine and a couple of routers. My question is about what private IP address ranges to use, currently they're as follows:- 2820n - 192.168.1.1 This has *everything* hanging on it, backup NAS, family computers, media boxes, etc. Speedtouch - 192.168.13.254 2820n WAN - 192.168.13.65 (assigned by Speedtouch DHCP) New dmz computer would be added to this LAN Would it be worth changing things around so that the Speedtouch LAN is 192.168.1.x (the almost universal default for home LANs) and the 2820n one is 192.168.13.0, or even 10.0.0.0 or 172.16.0.0 so that an intruder is less likely to guess that there's another LAN to look for? I know this is 'security by obscurity' to some extent but it's no effort really except some minor configuration changes to some static addresses and DHCP servers so if it offers any advantage it's probably worth doing. -- Chris Green

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Is there a better 'locate' anywhere?
by Chris Green 16 May '14

16 May '14

Does anyone else find that 'locate' does all the wrong things for them? It's not that it's incapable of doing what I want but the defaults seem to be set up to be purposely the opposite of what I actually need it to do. The defaults for 'find' on the other hand are almost exactly what I want to do when searching for files. When you give 'locate' a name to search for it finds everything with that string of characters in it, this nearly always results in zillions of hits I don't want. However 'find' only finds exact matches unless you specify an RE explicitly. Yes, I know that you can tell 'locate' to find only exact matches but the default is wrong for me. Secondly 'locate' searches the whole file system, I very rarely want to do this especially as there are incremental backups which produce dozens of near identical hits. With 'find' I can specify (have to specify in fact) the root of the search which again is nearly always exactly what I want to do. In this case it's much more difficult to make 'locate' work the same way as 'find' because you'd have to rebuild the database (I did do that once but my changes got lost in an upgrade I think). So, is there an alternative out there that works (by default preferably) like 'find' but uses a pre-built database like 'locate' so is reasonably fast? -- Chris Green

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FTP server with compression for large text files
by Mark Rogers 16 May '14

16 May '14

I need to set up an FTP server to host fairly large text files (.CSV). At the FTP client level these need to be uncompressed but I'd like to reduce server disk requirements by using compression. I guess I could either do this at a file system (FUSE) level or transparently within an FTP server, assuming there is an FTP server that can do this. Anyone got any experience with this or suggestions? -- Mark Rogers // More Solutions Ltd (Peterborough Office) // 0844 251 1450 Registered in England (0456 0902) @ 13 Clarke Rd, Milton Keynes, MK1 1LG

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Scrap IT kit
by Laurie Brown 13 May '14

13 May '14

Hi all, Does anyone on the list know of a company in East Anglia that buys scrap IT kit? Servers, desktops, routers, that sort of thing. I've got quite a lot to clear, and I don't really want to give it to the Council! Cheers, Laurie. -- --------------------------------------------------------------------- Laurie Brown laurie(a)brownowl.com ---------------------------------------------------------------------

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Re: [ALUG] What am I doing wrong?
by mark fernandes 11 May '14

11 May '14

But the mailing list page does point to this About.com page on setting various clients to plain-text http://email.about.com/od/netiquettetips/qt/When-In-Doubt-Send-Plain-Text-E… HTH, Mark

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Why do apache2 and leafnode need /etc/hosts configured with a FQDN?
by Chris Green 10 May '14

10 May '14

I have just moved dnsmasq from one machine to another, the machine I moved it from was only running dnsmasq so it was a bit of a waste of electricity and configuration maintenance. I'm now running dnsmasq on the machine where I also run apache2 and leafnode. Both leafnode and apache2 were perfectly happy before the dnsmasq move, they got a FQDN from dnsmasq presumably as there was nothing in the local /etc/hosts. Since moving dnsmasq to the same machine as leafnode and apache2 I've had to add a line:- 192.168.1.4 chris.zbmc.eu to my /etc/hosts, just chris won't do, even though dnsmasq delivers a correct FQDN with just chris. It's as if leafnode and apache2 go direct to /etc/hosts first. It's hardly a big deal but it just seems wrong somehow, why don't apache2 and leafnode use 'the proper channels'? -- Chris Green

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What am I doing wrong?
by Paul Lenton 10 May '14

10 May '14

Hi all, Every time I send a message to the ALUG list I get a bounceback saying that my message is awaiting moderation for a "suspicious header". Am I adding anything funny into my emails that is causing this? Cheers -- Paul GitHub - EckoZero https://github.com/eckozero Registered Linux user #557339 https://linuxcounter.net/user/557339.html

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Memtest86 always reports bad ram on a specific motherboard
by Srdjan Todorovic 10 May '14

10 May '14

Hi all, I've inherited an old Dell PowerEdge desktop, with 3GB DDR2 RAM in modules of 1GB. Naturally, I ran Memtest86 from one of the Ubuntu CDs. With all 3 RAM modules, memtest fails at approximately 50% of the whole test, at approximate offset of 128MB (40,000++ errors). I then tested each of those RAM modules in isolation, same result. I ran the test of 1 module in a different slot, same result. I then took one of my old DDR2 modules, and tested that in isolation, same result. I have no reason to suspect that my old DDR2 module is faulty. I ran memtest with that module some time ago in an old motherboard and had no issues. The ram was stored in an anti-static bag, but maybe it's possible for that old RAM module to get zapped in storage. Could it be possible that the RAM controller on the motherboard is partially damaged? I have ubuntu running on this machine, and so far no detectable problems. Could it be that memtest86 itself has a bug or cannot execute the tests correctly? >From what I remember, all the BIOS settings relating to RAM are set to auto, but even so the BIOS beeps at me on bootup saying that the memory configuration is not optimal. I am trying to decide if it's worth keeping it for an experimental box or just salvaging workable parts and recycling the rest. Thanks! Srdjan

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Any WordPress experts here - need help selecting a plugin
by Chris Green 10 May '14

10 May '14

I'm adding what is effectively a membership database to a WordPress site, there are a couple of special requirements:- 1 - The members can be individuals or organisations. An organisation member will have the organisation details - Name, address, phone, etc. - plus the ability to add up to five named individuals with simple details for each. 2 - It's a paid for membership so there will be a PayPal button for both individual and organisation membership, we obviously don't want to enter details for someone who hasn't paid. The PayPal buttons can have a 'Take customers to this URL when they finish checkout' option so this could be done by having a separate commit for the input form. The actual data for a member is pretty standard, nothing beyond Name, Address, E-Mail, Phone, etc. Looking for 'membership' or similar on the WP Plugins site pulls up hundreds of plugins all aimed at giving multi-level access to the web site which isn't what we need at all. So, any ideas anyone? I'm happy to customise an existing plugin, I can code in PHP reasonably well, but the more off-the-shelf it is the better of course. It feels like a good club membership database plugin would do but I can't find one in the morass of website membership plugins. -- Chris Green

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Can anyone suggest why this ssh connection only works sometimes?
by Chris Green 09 May '14

09 May '14

I have a Beaglebone Black system on our boat in France which is connected to the internet via a WiFi hotspot. To allow me to connect to it with ssh it is set up to create ssh tunnels to a couple of places where I have logins. I used to run something similar on an ancient eeePc, on that system it remained permanently accessible but on the Beaglebone Black it only allows me to connect some of the time. I have to repeatedly try to connect over a few minutes to get connected:- halon$ ssh -p 51234 localhost ssh_exchange_identification: Connection closed by remote host halon$ ssh -p 51234 localhost ssh: connect to host localhost port 51234: Connection refused halon$ while true; do ssh -p 51234 localhost; sleep 60; done ssh: connect to host localhost port 51234: Connection refused ssh: connect to host localhost port 51234: Connection refused chris@localhost's password: It's not that the ssh processes on the BBB are dying, they've been running for several days:- chris@beaglebone$ ps -ef | grep ssh root 968 1 0 May04 ? 00:00:00 /usr/sbin/sshd -D root 1262 1 0 May04 ? 00:00:01 /usr/lib/autossh/autossh -N -R 51234:localhost:22 -l chris cheddar.halon.org.uk root 1263 1 0 May04 ? 00:00:01 /usr/lib/autossh/autossh -N -R 51235:localhost:22 -l isbdnet3 shell.gridhost.co.uk root 1264 1 0 May04 ? 00:00:01 /usr/lib/autossh/autossh -N -R 51236:localhost:22 -l timetode shell.gridhost.co.uk root 3288 1264 0 11:13 ? 00:00:00 /usr/bin/ssh -L 34227:127.0.0.1:34227 -R 34227:127.0.0.1:34228 -N -R 51236:localhost:22 -l timetode shell.gridhost.co.uk root 9614 1262 0 18:17 ? 00:00:00 /usr/bin/ssh -L 34448:127.0.0.1:34448 -R 34448:127.0.0.1:34449 -N -R 51234:localhost:22 -l chris cheddar.halon.org.uk root 9727 968 3 18:20 ? 00:00:00 sshd: chris [priv] chris 9752 9727 0 18:20 ? 00:00:00 sshd: chris@pts/0 root 18064 1263 0 May08 ? 00:00:01 /usr/bin/ssh -L 61875:127.0.0.1:61875 -R 61875:127.0.0.1:61876 -N -R 51235:localhost:22 -l isbdnet3 shell.gridhost.co.uk So what could be making the tunnels work some of the time but not all of the time? -- Chris Green

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