dovecot unable to start due to address already in use - linux

I upgraded my Linux kernel and dovecot failed to start with the following error messages:
Error: service(managesieve-login): listen(*, 4190) failed: Address already in use
Error: service(pop3-login): listen(*, 110) failed: Address already in use
Error: service(pop3-login): listen(*, 995) failed: Address already in use
Error: service(imap-login): listen(*, 143) failed: Address already in use
Error: service(imap-login): listen(*, 993) failed: Address already in use
Fatal: Failed to start listeners
Strangely enough, I couldn't find any process bounded to those port numbers. All commands below return nothing.
# netstat -tulpn | grep 110
# ss -tulpn |grep 110
# fuser 110/tcp
# lsof -i :110
I also tried to change the listen setting to my specific IP address and it still failed the same way.
Any idea how I can solve this problem? Here's my version info:
# uname -a
Linux ip-172-31-26-222 4.14.177-107.254.amzn1.x86_64 #1 SMP Thu May 7 18:30:14 UTC 2020 x86_64 x86_64 x86_64 GNU/Linux
# dovecot --version
2.2.36 (1f10bfa63)

Hi it looks like you are using AWS as I am. I recently updated via Yum as well. I noticed that a new package named 'portreserve' was also installed. I killed that process, left the /etc/dovecot/dovecot.conf as it was before and then started Dovecot successfully. I was also immediately able to reconnect my mail clients connection. I hope that helps you.
I also restarted the portreserve program since it seems useful to limit port access.

Related

Cannot start J-Link GDB Server on Ubuntu

I am currently working on the ARM Cortex-M4 inside the NXP i.MX8M Mini.
I am able to compile a project for M4 on Eclipse IDE on an Ubuntu VM.
I would now like to debug on the M4 via a SEGGER Flasher ARM probe, still from Ubuntu.
My probe is well recognized by Ubuntu, and I can launch the J-Link GDB server by simply typing the command :
$ sudo ./JLinkGDBServerCLExe
However, if I type the same command without sudo, I get :
$ ./JLinkGDBServerCLExe
SEGGER J-Link GDB Server V7.58b Command Line Version
JLinkARM.dll V7.58b (DLL compiled Nov 16 2021 15:04:27)
-----GDB Server start settings-----
GDBInit file: none
GDB Server Listening port: 2331
SWO raw output listening port: 2332
Terminal I/O port: 2333
Accept remote connection: yes
Generate logfile: off
Verify download: off
Init regs on start: off
Silent mode: off
Single run mode: off
Target connection timeout: 0 ms
------J-Link related settings------
J-Link Host interface: USB
J-Link script: none
J-Link settings file: none
------Target related settings------
Target device: Unspecified
Target interface: JTAG
Target interface speed: 4000kHz
Target endian: little
Connecting to J-Link...
Connecting to J-Link failed. Connected correctly?
GDBServer will be closed...
Shutting down...
Could not connect to J-Link.
Please check power, connection and settings.
My problem is that when I start eclipse, I get the same result as starting the GDB server without sudo.
It seems that this is a rights issue, how can I solve it?
As #KamilCuk said, the problem came from the udev rules.
So you just have to copy the rules provided by Segger with J-Link Software on the system:
$ sudo cp 99-jlink.rules /etc/udev/rules.d
Then you have to reboot the system:
$ reboot

Which process sends SIGKILL and terminates all SSH connections on/to my Namecheap Server?

I've been trying to troubleshoot this problem for some days now.
A couple of minutes after starting an SSH connection to my Namecheap server (on Mac/windows/cPanel's "Terminal"), it crashes and give the following error message :
Error: The connection to the server ended in failure at {TIME} PM. (SIGKILL)
and :
Exit Code: 137
I've tried to create some kind of log file for any SIGKILL signal, but, it seems like none can be made on a Namecheap server :
auditctl doesn't exist,
We can't get systemtap because no package managers are available.
Precision :
uname -a : Linux [-n] 2.6.32-954.3.5.lve1.4.78.el6.x86_64 #1 SMP Thu Mar 26 08:20:27 EDT 2020 x86_64 x86_64 x86_64 GNU/Linux
I calculated the time between each crash : around 6min.
I don't have a very good knowledge of Linux servers, and maybe didn't include needed information. So please ask for any specificities!

NetworkManager conection disconected reason -3 issue

Today suddenly i receive this issue - sometimes i cant conect to any network, some time i cant conect to WPA2 networks, by can conect to unsecure network, some times i conect to everithing. Before 3 weeks i haven any problem.
In logs by journalctl -f | grep -i warn i see:
янв 12 14:16:08 egor-pc NetworkManager[572]: <warn> [1578831368.2657] device (wlp0s20f3): Deactivation failed: GDBus.Error:fi.w1.wpa_supplicant1.NotConnected: This interface is not connected
янв 12 14:16:08 egor-pc NetworkManager[572]: <warn> [1578831368.2662] sup-iface[0x55cd805be930,wlp0s20f3]: assoc[0x55cd80652b80]: abort due to disconnect: Request cancelled
янв 12 14:16:12 egor-pc NetworkManager[572]: <warn> [1578831372.0231] sup-iface[0x55cd805be930,wlp0s20f3]: connection disconnected (reason -3)
янв 12 14:17:18 egor-pc com.deepin.daemon.Accounts[683]: <warning> network.go:304: No such interface “org.freedesktop.DBus.Properties” on object at path /org/freedesktop/NetworkManager/Devices/4
If need, i can send more logs, or check something else. I try use sudo sh -c 'modprobe -r iwlwifi && modepobe iwlwifi 11n_disable=1' from UBUNTU forum but it now helps.
OS: Arch Linux x86_64
Kernel: 5.4.8-arch1-1
This thing helps me https://linuxconfig.org/unmanaged-network-solution-on-debian-linux
Maybe ilt helps to somebody else

Slurm and Munge "Invalid Credential"

I'm installing slurm for the first time. I've installed the 19.05.1-2 tarball and used the configurator to make a very simple two node cluster. Control node is sdc, compute nodes (running slurmd) are sdc and sdc1. Both rebuilt with Ubuntu 18.04
I can start the controller, and the compute node sdc and also successfully submit jobs with srun. That's great. However, when I start slurmd on the second node, SDC1, I get:
slurmd: error: Unable to register: Zero Bytes were transmitted or received
That quickly led me to my munge configuration. Munge.log on the controller (sdc) shows "Invalid credential" every second. I triple checked that munge.key on both hosts are identical. I verified that ntp is running too.
So by hand I did munge -s foobar | unmunge on SDC1 and of course that worked locally. Then I saved the munged text from SDC1 to a file on SDC and tried unmunge. That did give me the error "Invalid credential" again.
Because of this I uninstalled and reinstalled munge on both systems, distributed the key and repeated that test with the same result.
I guess I'm missing something simple. I don't know what else to do to properly install munge.
It was UID/GID mismatch between nodes. Of course it's mentioned in the installation guide.
Did you remember to restart the munge daemon after copying the munge.key to /etc/munge? I got the same error doing
1: install slurm:
$ apt install -y slurm-client
2: copy slurm.conf
(perhaps create slurm-llnl beforehand):
$ cp slurm.conf /etc/slurm-llnl
3: copy munge key to client
(munge.key copied before from slurm server/slurmctld)
$ cp munge.key /etc/munge
and then I got all the invalid credetial errors and problems reported here and in reports including the 'Zero Bytes' error on the client side
[CLIENT]$ sinfo
slurm_load_partitions: Zero Bytes were transmitted or received
with corresponding entries in the Slurm SERVER/slurmctld logs ala
[SERVER]$ tail /var/log/munge/munged.log
2022-12-30 22:57:23 +0100 Notice: Running on ..
2022-12-30 23:01:11 +0100 Info: Invalid credential ...
and
[SERVER]$ tail /var/log/slurm-llnl/slurmctld.log
[2022-12-30T23:01:11.440] error: Munge decode failed: Invalid credential
[2022-12-30T23:01:11.440] ENCODED: Thu Jan 01 01:00:00 1970
[2022-12-30T23:01:11.440] DECODED: Thu Jan 01 01:00:00 1970
[2022-12-30T23:01:11.440] error: slurm_unpack_received_msg: REQUEST_PARTITION_INFO has authentication error: Invalid authentication credential
[2022-12-30T23:01:11.440] error: slurm_unpack_received_msg: Protocol authentication error
All of this is fixed by rebooting the client, as suggested by other here, or slightly less intrusive, just to restart the client munge daemon
(CLIENT)$ sudo systemctl restert munge.service
and then munge on client / unmunge on server works, but it also fixes my main problem of getting client to see the slurm server without the dreaded 'Zero Bytes' error
[CLIENT]$ sinfo
slurm_load_partitions: Zero Bytes were transmitted or received
with server log entries
[SERVER]$ tail /var/log/slurm-llnl/slurmctld.log
...
[2022-12-30T23:17:14.017] error: slurm_unpack_received_msg: Invalid Protocol Version 9472 from uid=-1 at XX.XX.XX.XX:44150
[2022-12-30T23:17:14.017] error: slurm_unpack_received_msg: Incompatible versions of client and server code
[2022-12-30T23:17:14.027] error: slurm_receive_msg [XX.XX.XX.XX:44150]: Unspecified error
And, after munge restart, voilà:
[CLIENT] $ sinfo
PARTITION AVAIL TIMELIMIT NODES STATE NODELIST
LocalQ* up infinite 1 idle XXX
for the examples: SERVER Ubuntu 20.04, CLIENTS Ubuntu 20.04 (and 22.04 that seem to be incompatible with the SERVER slurm version, says the log)

"service networking stop" failed to stop on Ubuntu loaded as VM on Windows 7

I am running Ubuntu 64 bit on top of Oracle VM installed on Windows 7 Operating System.
This is the error message I am getting
stop: Rejected send message, 1 matched rules; type="method-call", sender=":1.10" (uid=1000) pid=1084 comm="stop networking"; interface="com.ubuntu.Upstart0_6.job" member="Stop" "error_name"="unset" requested_reply="0" destination="com.ubuntu.Upstart" (uid= 0 pid=1 comm="/sbin/init")
start: Rejected send message, 1 matched rules; type="method-call", sender=":1.11" (uid=1000) pid=1085 comm="stop networking"; interface="com.ubuntu.Upstart0_6.job" member="Stop" "error_name"="unset" requested_reply="0" destination="com.ubuntu.Upstart" (uid= 0 pid=1 comm="/sbin/init")
Is this because of any settings I misconfigured?
What exactly it could be?
I was trying to restart the networking service to get the eth1 interface working.
Instead of doing netwrking service restart it I just ran following command at the commandline.
$sudo ifup -v eth1
And the interface started showing up
Though this is not a solution but it worked for me. Still I dont know what was wrong above.

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