I installed usbmount package on ubuntu server lucid 10.04. It worked fine. I just plug in my USB flash. The server detects it and automatically mounts it under /media/usb0.
I want this USB folder to be available as samba share. I want it to be available to everyone with full control. The problem is that the usbmount mounts it using default permissions with root as owner.
Any idea how I can configure the usbmount to do this?
I am using backuppc to backup my server. The backups are done using rsyncd. Currently, I am not using ACLs, but I am think it is good to activate it to have finer control over permissions.
My question: Will backing up my files using rsync preserve the defined ACLs?
BTW, I read an article about ACLs. They are saying that ubuntu does not support ACLs with tar. Is this real/old or not? I may not have this problem if I am using rsync. Is this right?
I noticed that daily log rotations which are listed under /etc/logrotate.d/ are executed in the morning around 6:40 am. This is clear from the beginning and ending of the log files. Can I customize this time and set it to midnight for example?
It is nice to have one log file per day.
I am using ubuntu server 10.04 if that matters.
I have a running Ubuntu Server 10.04.1. When I tried to login to the server via ssh, I could not. Instead, I got connection refused error. I tried to ping the machine and I got reply! So, the clear reason is that SSH daemon is stopped.
After reboot, I was able to login to my server via ssh. After some time, I looked at my logs /var/log/syslog and found the following records:
Jan 16 10:57:09 myserver init: ssh main process ended, respawning
Jan 16 10:57:09 myserver init: ssh main process (2465) terminated with status 255
Jan 16 10:57:09 myserver init: ssh main process ended, respawning
Jan 16 10:57:09 myserver init: ssh main process (2469) terminated with status 255
Jan 16 10:57:09 myserver init: ssh main process ended, respawning
Jan 16 10:57:09 myserver init: ssh main process (2473) terminated with status 255
Jan 16 10:57:09 myserver init: ssh main process ended, respawning
Jan 16 10:57:09 myserver init: ssh main process (2477) terminated with status 255
Jan 16 10:57:09 myserver init: ssh main process ended, respawning
Jan 16 10:57:09 myserver init: ssh main process (2481) terminated with status 255
Jan 16 10:57:09 myserver init: ssh main process ended, respawning
Jan 16 10:57:09 myserver init: ssh main process (2485) terminated with status 255
Jan 16 10:57:09 myserver init: ssh main process ended, respawning
Jan 16 10:57:09 myserver init: ssh main process (2489) terminated with status 255
Jan 16 10:57:09 myserver init: ssh main process ended, respawning
Jan 16 10:57:09 myserver init: ssh main process (2493) terminated with status 255
Jan 16 10:57:09 myserver init: ssh main process ended, respawning
Jan 16 10:57:09 myserver init: ssh main process (2497) terminated with status 255
Jan 16 10:57:09 myserver init: ssh main process ended, respawning
Jan 16 10:57:09 myserver init: ssh main process (2501) terminated with status 255
Jan 16 10:57:09 myserver init: ssh respawning too fast, stopped
I searched for a similar problem/solution. Some people said that this is caused by the SSH daemon trying to start before networking and they suggest to change ListenAddress in /etc/ssh/sshd_config to be 0.0.0.0. I think this is not the cause in my case, because my problem occurs after system is up and running.
Any idea what is causing this? This is Ubuntu Server and it should be running and accessed remotely using SSH.
UPDATE:
Here is the log snippet I found in /var/log/auth.log.
Jan 16 10:56:38 myserver sudo: user : TTY=pts/0 ; PWD=/home/user ; USER=root ; COMMAND=/usr/bin/vim /etc/ssh/sshd_config
Jan 16 10:57:09 myserver sudo: user : TTY=pts/0 ; PWD=/home/user ; USER=root ; COMMAND=/etc/init.d/ssh reload
Jan 16 10:57:09 myserver sshd[1465]: Received SIGHUP; restarting.
Jan 16 10:57:09 myserver sshd[2461]: Server listening on 0.0.0.0 port 22.
Jan 16 10:57:09 myserver sshd[2465]: error: Bind to port 22 on 0.0.0.0 failed: Address already in use.
Jan 16 10:57:09 myserver sshd[2465]: fatal: Cannot bind any address.
Jan 16 10:57:09 myserver sshd[2469]: error: Bind to port 22 on 0.0.0.0 failed: Address already in use.
Jan 16 10:57:09 myserver sshd[2469]: fatal: Cannot bind any address.
Jan 16 10:57:09 myserver sshd[2473]: error: Bind to port 22 on 0.0.0.0 failed: Address already in use.
Jan 16 10:57:09 myserver sshd[2473]: fatal: Cannot bind any address.
Jan 16 10:57:09 myserver sshd[2477]: error: Bind to port 22 on 0.0.0.0 failed: Address already in use.
Jan 16 10:57:09 myserver sshd[2477]: fatal: Cannot bind any address.
Jan 16 10:57:09 myserver sshd[2481]: error: Bind to port 22 on 0.0.0.0 failed: Address already in use.
Jan 16 10:57:09 myserver sshd[2481]: fatal: Cannot bind any address.
Jan 16 10:57:09 myserver sshd[2485]: error: Bind to port 22 on 0.0.0.0 failed: Address already in use.
Jan 16 10:57:09 myserver sshd[2485]: fatal: Cannot bind any address.
Jan 16 10:57:09 myserver sshd[2489]: error: Bind to port 22 on 0.0.0.0 failed: Address already in use.
Jan 16 10:57:09 myserver sshd[2489]: fatal: Cannot bind any address.
Jan 16 10:57:09 myserver sshd[2493]: error: Bind to port 22 on 0.0.0.0 failed: Address already in use.
Jan 16 10:57:09 myserver sshd[2493]: fatal: Cannot bind any address.
Jan 16 10:57:09 myserver sshd[2497]: error: Bind to port 22 on 0.0.0.0 failed: Address already in use.
Jan 16 10:57:09 myserver sshd[2497]: fatal: Cannot bind any address.
Jan 16 10:57:09 myserver sshd[2501]: error: Bind to port 22 on 0.0.0.0 failed: Address already in use.
Jan 16 10:57:09 myserver sshd[2501]: fatal: Cannot bind any address.
It seems that this error started to appear after I reloaded the SSH daemon. Should I avoid using ssh reload and use ssh restart instead?
I have a small question regarding using sudo with output redirect >. To enable IP forwrding, someone can use the command:
echo 1 > /proc/sys/net/ipv4/ip_forward
Executing this command will give permission denied as it requires root privileges. However, executing the same command with sudo gives also permission denied error! It seems that output redirect > does not inherit the permissions of the preceding command echo. Is this right?
As a workaround I do:
echo 1 | sudo tee /proc/sys/net/ipv4/ip_forward
Is this the best way to do it? Am I missing something?
Please, note that this is an example and it applies to all commands that use output redirect.
I installed nagios3 on ubuntu server 10.04.1. It was working fine.
Today, I found it stopped and when I tried to start it using sudo /etc/init.d/nagios3 start, it did not start. I found this in the log file:
Nagios 3.2.0 starting... (PID=11729)
Local time is Wed Dec 22 14:15:31 2010
Caught SIGSEGV, shutting down...
I tried to remove and re-install it without success. After googling, it seems that no one has a solution for this. I don't want to install it from source unless it is really the last hope.
I have several Ubuntu servers. Two of them are working as DNS servers. One of my name servers (let's call it DNS1) went down for maintenance. I sill had another DNS server running (DNS2).
All other servers are configured to use the nameservers as follows
/etc/resolv.conf :
nameserver DNS1
nameserver DNS2
I can still resolve DNS names using the DNS2 server, but the name resolution takes a long time. It is clear to me that any given server is first trying to access DNS1, and then it is trying DNS2 after failure.
I tried to swap the two lines. The name resolution became too fast.
I am wondering if there is a way to dynamically change the resolv.conf file based on the state of the configured nameservers. Of course, I can write a shell script myself to do the job. But I prefer to find a better way if there is one.
As it is well known, it is recommended that the system administrator login to the system using a normal user (non-root). When the admin needs to do privileged tasks, sudo can be used to become superuser. Before gaining the requested privileges, the admin will be prompted to enter the SAME password used in the first login.
I was wondering whether it is possible to configure the system to ask the user for a different password when doing sudo. So, the user will have two passwords. The first password will provide access to SSH session. The other password (not the same one) will be used to gain the admin (root) privileges.
Is this possible? I think it will add more security to the system. Do you agree?
BTW, this will be similar to the access control used by Cisco devices. First, the admin login using a password. Then, accessing "enabled" (privileged) mode requires another password (can be different or same password).
Is it possible to install packages using apt-get install without having HTTP access? In other words, can apt-get install packages from a small local repository?
I know I can use sudo dpkg -i deb_file to install a package, but this will install only one package at a time and it will fail if the dependencies are not met. This will be a problem if I want to install a package that has many dependencies even if I already have all the required .deb files.
I installed NTP server on Ubuntu Server 10.04 using:
sudo apt-get install ntp
The NTP daemon seems working and listening on the 123 port.
However, I was not able to get the time from another machine:
sudo ntpdate -u my_ntp_server
23 Nov 18:48:41 ntpdate[2990]: no server suitable for synchronization found
Is there any necessary configurations to do?
I installed ubuntu server 10.04 and booted as normal.
Some time later, I booted the server and tried to install a new package/upgrade the existing packages using:
sudo apt-get upgrade
sudo aptitude safe-upgrade
sudo apt-get install ntp
Reading package lists... Done
Segmentation faulty tree... 50%
I checked the system log /var/log/messages and found these entries:
kernel: [ 5586.184028] apt-get[3864]: segfault at 7fb5e078477b ip 00007fb5da82223c sp 00007fffa943b430 error 6 in libapt-pkg-libc6.10-6.so.4.8.0[7fb5da7e1000+c5000]
kernel: [ 5682.494467] aptitude[3973]: segfault at 7f06d4c4d77b ip 00007f06d063723c sp 00007fff5feb8540 error 6 in libapt-pkg-libc6.10-6.so.4.8.0[7f06d05f6000+c5000]
kernel: [ 5991.238428] apt-get[4181]: segfault at 7f809c17e77b ip 00007f809621c23c sp 00007fff740deb30 error 6 in libapt-pkg-libc6.10-6.so.4.8.0[7f80961db000+c5000]
Also, I got the same error while trying to use aptitude safe-upgrade as it is clear from the log file.
How can this be fixed without system re-installation?
I installed ubuntu server 10.04 on a PC with two HD drives 500 GB each. I used raid1 to provide data protection. The /boot partition is installed also on a mirrored device /dev/md0.
After the installation has completed, the system did not boot properly. I got the following error message:
ALERT! /dev/disk/by-uuid/<long characters> does not exist. Dropping to a shell!
Any idea what could cause such a problem?
UPDATE:
I booted into rescue mode using the installation CD. Executing fdisk showed me the partitions, but it said "Partition 1 does not end on cylinder boundary.". Can this be related to the problem at hand?
UPDATE2:
I re-installed ubuntu server without the Raid at all. The system booted as it should be! Also, I got the same error from fdisk after booting. So, this error should not be related to this problem of not being able to boot.
It is puzzling me. Can't I install ubuntu server 10.04 with raid1?!!