úterý 29. července 2025

multi-hop gateway in wireguard (hub and spoke)

https://www.procustodibus.com/blog/2022/06/multi-hop-wireguard/#internet-gateway-as-a-spoke 

routovani default routy skrz wireguard mezi peerama:

on the client, 172.20.24.15 set 

wg0.conf
[Interface] ... Address = 172.20.24.15/32
[Peer] ... AllowedIPs = 0.0.0.0/0 

ip route add wg_server_ip via 192.168.122.1 dev eth0
ip route add default via 172.20.24.10 dev wg0 

 

on the gateway, 172.20.24.10 

iptables -t nat -A POSTROUTING -s 172.20.24.0/24 -o vlan2 -j MASQUERADE
(a mozna i neco z toho:
iptables -t nat -A POSTROUTING -o oet1 -j MASQUERADE
iptables -A FORWARD -i oet1 ...? ) 

(list:  iptables -t nat -S POSTROUTING )

on the hub (wg server) 172.20.24.1 

wg:
wg set wg2 peer rdwrtQdE7Z0SqZcJmoydFD74vXLLTnf+gk9go5pDWRw= allowed-ips 0.0.0.0/0 (namisto 172.20.24.10/24) (klic je klienta gateway) 

routing:
echo "123 wgfrompeer" >> /etc/iproute2/rt_tables #tim se nastavi jen jmeno
ip route add default via 172.20.24.10 dev wg2 table 123
ip rule add iif wg2 table 123 priority 100

(list:  ip route show table 123 , ip rule show )

 

firewall:
# neco z tohodle:
sysctl -w net.ipv4.ip_forward=1 (to uz je zrejme jako default)
iptables -A FORWARD -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT
iptables -A FORWARD -i wg2 -s 172.20.24.0/24 -j ACCEPT
iptables -I FORWARD -i wg2 -o wg2 -j ACCEPT

středa 5. března 2025

File browser and file dialogs take a long time to open

 https://askubuntu.com/questions/1341909/file-browser-and-file-dialogs-take-a-long-time-to-open-or-fail-to-open-in-all-ap

 

Fast solution: 

pkill gvfsd-trash

Brute force permanent solution:

mv /usr/libexec/gvfsd-trash{,.bak}

 

úterý 3. září 2024

override ownership of mounted filesystem

 According to How can I mount a filesystem, mapping userids? :

I need to mount image file and share the content in the samba tree.

The thus, I need to remap original "user" to local user "nobody".

 

 

apt install  bindfs
root# mount -o ro /dev/loop1 /mnt/1 
root# bindfs -u nobody -g nogroup --map=user/nobody /mnt/1 /data/samba/tree/mountpoint

pátek 9. srpna 2024

Ansys 57 on 64-bit Debian 12 Bookworm

1. copy old installation tree

2. try it it runs:

 ~$ /ansys_inc/ansys57/bin/xansys57
bash: /ansys_inc/ansys57/bin/xansys57: cannot execute: required file not found

or:

 ~$ LM_LICENSE_FILE=1057@server /ansys_inc/ansys57/bin/ansys57 < inputfile.inp

If this works, change the variable definition: setenv ANSYSLIC_DIR /ansys_inc/ansys57
in /ansys_inc/ansys57/bin/anscript57.ini
and create the license file

echo SERVER=1057@server > /ansys_inc/ansys57/ansyslmd.ini 

3. add missing binaries

# apt install ncompress tcsh
# dpkg --add-architecture i386
# apt-get update
# apt install libc6-i386

ldd command lists missing libraries:

# ldd /ansys_inc/ansys57/bin/linuxia32/xans.e57
....
# apt-get install   libxi6:i386
# apt-get install   libxt6:i386
# apt-get install   libxpm4:i386
# dpkg -L  libxpm4:i386
# ln -s /usr/lib/i386-linux-gnu/libXpm.so.4.11.0 /usr/lib/i386-linux-gnu/libXp.so.6

# The Motif library libXm.so.2 is included in the original tree in a rpm file: extract libraries from

/ansys_inc/ansys57/syslib/OPENMOTIF/openmotif-2.1.30-2_ICS.i386.rpm
/ansys_inc/ansys57/syslib/MESA/Mesa-3.2-1rh61.i386.rpm

into /ansys_inc/ansys57/syslib/linuxia32 folder and create symlink:

cd /ansys_inc/ansys57/syslib/linuxia32
ln -s libXm.so.2.1 libXm.so.2

goto 2.

ansys 2024 "error while loading shared libraries: libXp.so.6: cannot open shared object file" (Debian 12 Bookworm)

ANSYS 2024R1, R2 does not start after installation due to missing libraries:

error while loading shared libraries: libXp.so.6: cannot open shared object file:

actually, the library is present in the installed tree

/ansys_inc/v242/ansys/syslib/ubuntu/libXp.so.6.2.0 

 

The ANSYS startup script anssh.ini adds the correct path to the LD_LIBRARY_PATH only when it detects Ubuntu OS. The check is done by 

grep Ubuntu /etc/os-release

So that it is sufficient to add a line to that file (yes, it is a dirty hack)

echo '# fake id to fool Ansys: Ubuntu' >> /etc/os-release