- main - earth.li

Display error when switching to console from X
by Chris G 27 Nov '08

27 Nov '08

I'm running xubuntu 8.10 (though I suspect the problem is common to all 8.10 ubuntu versions). I can run X fairly reliably though I do have some issues when logging in and out presumably due to switching resolutions. However switching to a console using CTRL/ALT/F1 (or any of the others) doesn't work. I just get an error message from my monitor saying the resolution is invalid. My monitor is a Dell 2001FP capable of up to 1600x1200 so I suspect that the CTRL/ALT/F1 is switching to a totally impossible resolution. How can I fix this problem? Is there any way to specify the mode and resolution to use for the text mode consoles? -- Chris Green

2 4

[Fwd: Re: Display error when switching to console from X]
by Stevey.eu 27 Nov '08

27 Nov '08

On Thu, Nov 27, 2008 at 11:03:46AM +0000, Stevey.eu wrote: > > Chris G wrote: >> >> I'm running xubuntu 8.10 (though I suspect the problem is common to >> >> all 8.10 ubuntu versions). >> >> I can run X fairly reliably though I do have some issues when logging >> >> in and out presumably due to switching resolutions. >> >> However switching to a console using CTRL/ALT/F1 (or any of the >> >> others) doesn't work. I just get an error message from my monitor >> >> saying the resolution is invalid. My monitor is a Dell 2001FP capable >> >> of up to 1600x1200 so I suspect that the CTRL/ALT/F1 is switching to a >> >> totally impossible resolution. >> >> How can I fix this problem? Is there any way to specify the mode and >> >> resolution to use for the text mode consoles? >> >> > > Chris, > > > > Ever considered trying www.google.com it is a marvelous invention. > > Strangely enough I am familiar with Google, I'd recommend using www.google.co.uk personally, it does offer advantages for UK users sometimes (although not in this case of course). I have spent quite a lot of time searching around using Google on this issue and have follwed a few leads but I don't have a solution yet. Asking on alug was just another approach. -- Chris Green

2 2

What does 'seahorse' actually do?
by Chris G 27 Nov '08

27 Nov '08

Having just changed my login password on my new Linux box I have discovered that there's an application called 'seahorse' lurking in the background. After changing my password seahorse pops up a window when you log in to X demanding that you enter a password - what it's asking for is the *old* password which it has stashed away somewhere itself. What isn't clear though is what seahorse is for and reading the Help is no 'help' at all, it just tells you how to drive the program, which is fine in itself but doesn't help me at all in working out what it does. Can anyone here help? Does seahorse do the same as ssh-agent? Does it do it 'automagically' when you log in to X using your login password? I've found the seahorse home page http://projects.gnome.org/seahorse/index.html and that tells me just about nothing. The best there is (on the 'about' page) is:- With seahorse you can... * Create and manage PGP keys * Create and manage SSH keys * Publish and retrive keys from key servers * Cache your passphrase so you don't have to keep typing it * Backup your keys and keyring * more... It's rather a fundamental security thing to 'just happen' behind your back! -- Chris Green

1 0

sSMTP
by Torben Stones 26 Nov '08

26 Nov '08

I'm trying to setup sSMTP on a small home server, so that I can get the output from the cron jobs e-mailed to me. I believe that I've got it all setup correctly, as the message seems to be sent, but I'm never reciving anything. The config is so that every thing is sent to my gmail account and I'm useing smtp.googlemail.com as the smtp server. I'm trying to test using the command echo "Hello from sSMTP" | sendmail -v root >From the output it looks like it is working OK, but nothing ever arives. Has anyone set this up using google and/or does anyone have any idea as what I can check next. Thanks Torben -- You've got a lot of choices in your life. If getting out of bed in the morning is a chore and you're not smiling on a regular basis, try another choice.

2 1

PHP memory limit problem
by Chris G 25 Nov '08

25 Nov '08

I need to raise my memory limit as an upgrade of Gallery2 is failing due to running out of memory. I've increased the memory_limit in /etc/php5/apache2/php.ini to 256M but something else is preventing this from working. Running phpinfo() shows the following information (among other things):- Loaded Configuration File /etc/php5/apache2/php.ini additional .ini files parsed /etc/php5/apache2/conf.d/gd.ini, /etc/php5/apache2/conf.d/mcrypt.ini, /etc/php5/apache2/conf.d/mysql.ini, /etc/php5/apache2/conf.d/mysqli.ini, /etc/php5/apache2/conf.d/pdo.ini, /etc/php5/apache2/conf.d/pdo_mysql.ini Local Value Master Value memory_limit 24M 256M So, what's reducing the "Local Value" to 24M? There's nothing in those other "additional .ini files parsed", has apache2 got some sort of limit of its own somewhere? How can I find what's limiting it? -- Chris Green

1 1

Security - part II
by Chris G 25 Nov '08

25 Nov '08

I.e. thoughts and questions on backups. Continuing on from making my system secure against the most likely attacks etc. I need to make backups of the 'important' data. Currently I backup from my main server system (the pre-update one at the moment) to a system on the home LAN in the garage. The garage is a fair way from the house so in the event of a serious disaster (e.g. a fire) it should survive. I also backup the *most* important files off-site to my account at my hosting provider. At the moment these backups are 'pushed' from the main system, i.e. it is cron in that system that runs the backups. This requires that I have passwordless access to the destination system and here I see a hole! If a hacker got into my main system [s]he could immediately gain access to the backup destinations as well and destroy data there. How can one overcome this issue? I can see a partial way around it for the LAN backups, I can remove the passwordless access to the system in the garage and change to a 'pull' backup that is run by cron on the garage system. The garage system can have passwordless access to the main system to enable this, there's no access through the firewall to the garage system so a hacker would need to guess the garage system passwords to get to it. This at least provides another layer of pretection against malicious attacks. However I can see no way to pretect the off-site (across the internet) backups from similar attacks. If the shell account at my hosting provider was to have passwordless access to my home system that would lay me open to all sorts of malicious attacks so obviously that's not possible so I can't use the 'pull' backup from there. If I'm going to backup as at present the passwordless access to the off-site system needs to remain and therefore is open to a malicious attacker. It occurs to me that I could *possibly* do the backups from the garage system to the off-site system, that would improve things somewhat. How does the world at large do backups to remote systems without incurring security problems? -- Chris Green

4 7

ALUG Ipswich Xmas Meal 2008
by samwise 25 Nov '08

25 Nov '08

Hi, At the last Ipswich meet we discussed repeating the Xmas meal we had last year. Would anyone else on the list be interested in attending? We talked about having it on a different day to the usual December meet so if anyone else wants to join in, drop me a line and I'll try and co-ordinate a day that fits for everyone. Cheers, Peter.

1 0

Is it possible to use DHCP for DNS only?
by Chris G 25 Nov '08

25 Nov '08

Is it possible to set up a Linux system so that it has a fixed IP address on the LAN but uses the addresses given to it by a router (using DHCP) for DNS? -- Chris Green

5 12

mySql - problems with passwords etc., is there no easy way?
by Chris G 24 Nov '08

24 Nov '08

I always seem to get in a tangle with installing and setting up mySql. The essential problem seems to be that mySql wants to refer to the local machine as 'localhost', and 127.0.0.1, and 'chris'. Thus when I try and add a user it seems that the user gets added with privileges for one (or some) but not all of 'localhost', and 127.0.0.1, and 'chris' and then doesn't work because I need to acces the database as one of the other host names. Adding a user as 'user'@* seems to be even worse and doesn't work at all. I also seem to be having trouble changing the password for the mySql super user, I tried doing it via phpmyadmin and that seems to have done nothing, I can't quite fathom the syntax for doing it in mySql from the command line in the mysql front-end. I *do* know SQL fairly well and usually once I have the password/host chaos sorted out mysql works well for me but this part of it really stinks IMHO when you're working on localhost (or is it 127.0.0.1 or is it chris?). It's fine when working remotely, there's only one possible name for the place where the database is. -- Chris Green

3 4

Some thoughts/questions re: ssh security
by Chris G 24 Nov '08

24 Nov '08

As I'm in the process of moving my 'home server' across to a new machine it seems a good time to check out the security aspects. The machine runs behind an ADSL router which provides the firewall. I have the firewall set up so that the only access allowed from outside the home LAN is:- ssh port access from two specific IP addresses http and https access from anywhere I have data on the machine which I don't want to lose but it's not valuable or particularly confidential so I don't think I need to protect myself against concerted attacks from the CIA or MI5. :-) What I do want to prevent as far as possible is malicious attacks from hackers who, if they did get access, would probably just 'make a mess of things' for fun. The two IP addresses from which ssh access is allowed are the public address of my work machine and a machine where I have a shell login at my hosting company. Thus they are both moderately secure themselves but there is always a possibility that someone 'unfriendly' might get access. The choice (for ssh) lies between public/private key and ordinary passwords. I *know* that in general public/private key is regarded as more secure but I'm leaning towards using password security for the following reasons:- The machine where the password shadow file is stored is (relatively) secure, the only user is me. If someone (hacker) has access to the shadow file to apply brute-force/dictionary attacks then I've already lost the battle. I make very sure that passwords on my home machine bear no similarity to those on systems outside so knowledge of my 'outside' passwords will not make guessing my home machine's passwords easy. Someone who has access to my work/hosting accounts may well get access to the public key part of the public/private key pair. This, ultimately, lays it open to attack. They have *no* access to my home machine and thus, although the shadow file is fundamentally weaker in itself there is no opportunity at all to attack it. The *only* way that an attacker can break in is by guessing passwords. Does the above make reasonable sense or have I overlooked anything obvious? Obviously physical security matters and also I need to have the 'other half' of security based on backups etc. (probably subject of another E-Mail). Final question, how vulnerable does running apache2 on the system with general access make it? Are buffer overflow exploits and other such things likely to make my careful ssh security pointless? -- Chris Green

1 0