I have a linux system that is using Active Directory (2012) for LDAP lookups of users and groups. It's in a network that is connected to our main site by VPN.
When the VPN goes down, all ldap queries start failing. By running ss in a loop while removing this connection, I was able to see that the linux host is trying to make connections to AD servers that are not specified anywhere in ldap.conf.
Does anyone know what would be causing this to happen, and how it can be prevented?
As part of an OS deployment, I need to maintain sets of debian packages independently of the host operating system. It's pretty straightforward to override the Apt settings for the cache and lists, but not the dpkg setting for the admindir. For example:
apt-get -o Dir::Etc::Sourcelist='/path/to/sources.list' \
-o Dir::Cache::Archives='/path/to/cache/apt/archives' \
-o Dir::State::Lists='/path/to/lib/apt/lists' \
-o DPkg::Options::='--admindir=/path/to/lib/dpkg' update
This correctly reads my sources out of /path/to/sources.list, and builds the package available lists in /path/to/lib/apt/lists/*. However, at the end of the update command, I still get the following error:
E: Could not open lock file /var/lib/dpkg/lock - open (13: Permission denied)
This is despite the last option attempting to override the default dpkg admindir of '/var/lib/dpkg'. What am I doing wrong? According to guides like this, what I'm doing with DPkg::Options ought to work.
I know how to do the opposite (find out what process has a given port open) using lsof or netstat, but extensive research on Google hasn't helped me solve the reverse problem.
I know I could use "netstat -np" combined with some grep and sed, but it seems hacky. Is there a reversed version of "lsof -i tcp:80" that will show me all the local ports opened by a given process?
For reasons too complex to get into here, I'm using a 3-disk RAID1E on some linux systems. See here for more info on that.
So my understanding is that for optimizing filesystem layout on this volume, you use the following calculation:
chunk-size = 64kB
block-size = 4kB
stride = chunk / block = 16
stripe-width = stride * ( (numdisks)/2 ) = 16 * 1.5 = 24
However, mkfs.ext3 gives a warning when I use that calculation for setting the stripe-width, that it should be a power of two.
So my question is, am I doing it right? Should I be treating it like a standard four-disk RAID10, since the stripes are of the same size?
Update: it's not a degraded array, it's a fully supported configuration. Read the link from the first paragraph.
I do a lot of shell scripting in linux (running xmonad window manager, so I can use xmodmap or xinput, but not GNOME or KDE control panels), and it would be super useful for a shift-space keystroke to output an underscore ("_") character. Any ideas how to do this?
I'm working with a linux application which needs to talk with a remotely-located serial (rs-232) device. I've worked out how to use socat on the remote end to send the device's serial data over an IP connection, but how do I then convert that IP stream back into a (pseudo) serial device character device (e.g. /dev/fakesocatserial0) on the other side?