When ssh into a server I want to start directly tmux or use an existing session.
ssh example.local -t "tmux a || tmux"
Welcome to my world
When ssh into a server I want to start directly tmux or use an existing session.
ssh example.local -t "tmux a || tmux"
While trying to connect to an older esxi server I got the error message Unable to negotiate with 1.2.3.4 port 22: no matching host key type found. Their offer: ssh-rsa,ssh-dss
I was wondering.
The solution $EDITOR ~/.ssh/config
Host 1.2.3.4 User root HostKeyAlgorithms=+ssh-dss
The error message on the proxmox gui
() Job for ceph-mgr@pve-03.service failed. See "systemctl status ceph-mgr@pve-03.service" and "journalctl -xe" for details. TASK ERROR: command '/bin/systemctl start ceph-mgr@pve-03' failed: exit code 1
The error message from systemctl
ceph-mgr@pve-03.service: Start request repeated too quickly. ceph-mgr@pve-03.service: Failed with result 'start-limit-hit'.
Solve with
systemctl reset-failed ceph-mgr@pve-03 systemctl start ceph-mgr@pve-03
change pve-03 to your node name.
zfs send ... | ssh host2 zfs receive -s otherpool/new-fs
On the receiving side, get the opaque token with the DMU object #, offset stored in it
zfs send ... | ssh host2 zfs receive -s otherpool/new-fs zfs get receive_resume_token otherpool/new-fs # 1-e604ea4bf-e0-789c63a2...
Re-start sending from the DMU object #, offset stored in the token
zfs send -t 1-e604ea4bf-e0-789c63a2... | ssh host2 zfs receive -s otherpool/new-fs
If you don’t want to resume the send, abort to remove the partial state on the receiving system
zfs receive -A otherpool/new-fs
Edit
/etc/zfs/zed.d/zed.rc
uncomment
ZED_EMAIL_ADDR="mail@example.com"
and add a valid email address.
uncomment
ZED_EMAIL_PROG="mail"
uncomment
ZED_EMAIL_OPTS="-s '@SUBJECT@' @ADDRESS@"
uncomment
ZED_NOTIFY_VERBOSE=0
if you want to get an email after every scrup set the value to 1
save the file and restart zed service
systemctl restart zed.service
A single disk zpool “test” crashed on my server (the disk died). It was just for testing, so nothing dramatic. However, when I rebooted the server I got the error message “failed Import ZFS pools by cache file”. A zpool destroy -f did not solve the problem. zpool status still showed the “test” pool. The other pool tank was still working.
What did help was
# disable the cache file for the existing pool(s) zpool set cachefile=none tank # delete the old pool file rm -rf /etc/zfs/zpool.cache # recreate if touch /etc/zfs/zpool.cache reboot # re-enable the cache zpool set cachefile=/etc/zfs/zpool.cache tank
Well, the cache file should be automatically updated when your pool configuration is changed, but with the crashed pool it did not.
After virtualizing a real computer with an old Linux I wanted to increase the partition size of the data drive. But I got this warning: resize2fs new size too large to be expressed in 32 bits
How to solve this? I started the VM with gparted-live.iso
# check file system e2fsck -f /dev/sdb1 # auf 64 bit ändern resize2fs -b /dev/sdb1 # increase partition .... wait :D / optional coffee resize2fs -p /dev/sdb1 # check file system e2fsck -f /dev/sdb1
Done :)
How to do things with iptables. Safety first: How to reset everything.
sudo iptables -F sudo iptables -X sudo iptables -t nat -F sudo iptables -t nat -X sudo iptables -t mangle -F sudo iptables -t mangle -X
sudo iptables -A INPUT -p tcp -s localhost --dport 3306 -j ACCEPT #mysql allow local sudo iptables -A INPUT -p tcp --dport 3306 -j REJECT --reject-with tcp-reset #mysql
The “REJECT –reject-with tcp-reset” looks to the outside like there is no service running. A “DROP” will show that there is a firewall / iptables working.
Blocking an IP range
sudo iptables -A bannedDownloader -s 14.120.0.0/16 -j DROP
Disallow NTP queries
sudo iptables -A INPUT -p udp -s localhost --dport 123 -j ACCEPT #ntp allow local sudo iptables -I INPUT -p udp --dport 123 -j REJECT #ntp
Block timestamp
sudo iptables -I INPUT 1 -p ICMP --icmp-type timestamp-request -j DROP sudo iptables -I INPUT 1 -p ICMP --icmp-type timestamp-reply -j DROP sudo iptables -A INPUT -p icmp --icmp-type 13 -j DROP
remove lines starting with string
:g/^1.2.3.4.*$//d
remove all empty lines
:g/^$/d
:g/profile/d
delete line that contains “profile”
Now there Debian available over the Microsoft Store on Windows 10. Very small RAM usage, much better than the ubuntu version.
Open PowerShell as Administrator and run:
Enable-WindowsOptionalFeature -Online -FeatureName Microsoft-Windows-Subsystem-Linux
Then Open the Microsoft Store and search for debian.
The File are now in C:\Users\%USERNAME%\AppData\Local\Packages\TheDebianProject.DebianGNULinux_*
I wonder why it is no longer in C:\Users\%USERNAME%\AppData\Local\lxss\
For having correct displayed german characters I had to change the console
sudo dpkg-reconfigure locales sudo apt install console-setup sudo dpkg-reconfigure console-setup