M.Ch.'s questions

I have a weird PING error in WSL2, Ubuntu 20.04 distribution. When I'm doing nslookup - all ok:

root@i:~# nslookup google.com
Server:         172.19.224.1
Address:        172.19.224.1#53

Non-authoritative answer:
Name:   google.com
Address: 142.250.185.206
Name:   google.com
Address: 2a00:1450:4001:830::200e

root@i:~#

When I'm pinging by address - also ok:

root@i:~# ping 142.250.185.206
PING 142.250.185.206 (142.250.185.206) 56(84) bytes of data.
64 bytes from 142.250.185.206: icmp_seq=1 ttl=113 time=45.9 ms
64 bytes from 142.250.185.206: icmp_seq=2 ttl=113 time=45.1 ms
64 bytes from 142.250.185.206: icmp_seq=3 ttl=113 time=45.1 ms
^C
--- 142.250.185.206 ping statistics ---
3 packets transmitted, 3 received, 0% packet loss, time 2003ms
rtt min/avg/max/mdev = 45.066/45.382/45.941/0.396 ms
root@i:~#

But when I'm trying to PING by name - get error:

root@i:~# ping google.com
ping: google.com: System error
root@i:~#

Strace tells me something about "access denied", but what could deny this access? Can't find anything about that. https://pastebin.com/SpDZuX1c - strace with error
This:

openat(AT_FDCWD, "/etc/nsswitch.conf", O_RDONLY|O_CLOEXEC) = -1 EACCES (Permission denied)
stat("/etc/resolv.conf", 0x7ffea50eddb0) = -1 EACCES (Permission denied)
openat(AT_FDCWD, "/etc/host.conf", O_RDONLY|O_CLOEXEC) = -1 EACCES (Permission denied)
openat(AT_FDCWD, "/etc/resolv.conf", O_RDONLY|O_CLOEXEC) = -1 EACCES (Permission denied)

is really weird.

All files must be accessible:

root@i:~# stat /etc/resolv.conf
  File: /etc/resolv.conf
  Size: 198             Blocks: 8          IO Block: 4096   regular file
Device: 810h/2064d      Inode: 90071       Links: 1
Access: (0644/-rw-r--r--)  Uid: (    0/    root)   Gid: (    0/    root)
Access: 2022-02-04 16:14:10.859833659 +0300
Modify: 2022-02-04 15:43:48.419820525 +0300
Change: 2022-02-04 15:43:48.419820525 +0300
 Birth: -
root@i:~# stat /usr/bin/ping
  File: /usr/bin/ping
  Size: 72776           Blocks: 144        IO Block: 4096   regular file
Device: 810h/2064d      Inode: 7392        Links: 1
Access: (0755/-rwxr-xr-x)  Uid: (    0/    root)   Gid: (    0/    root)
Access: 2022-02-04 10:43:28.684002234 +0300
Modify: 2020-01-31 02:11:23.000000000 +0300
Change: 2022-02-04 10:43:21.754002185 +0300
 Birth: -
root@i:~#

root@i:~# getcap /usr/bin/ping
/usr/bin/ping = cap_net_raw+ep
root@i:~#

PING run from root.
Cannot enable auditd because its WSL.

curl, traceroute, nslookup, telnet - all is working perfectly, only PING has problems.
I'm totally confused and don't know where to look and what to fix.

Could someone provide any idea, how could i pipe data from nc to sed (or awk, or anything) and evaluate and write to file a timestamp after each row? What i have:

# cat /etc/systemd/system/ncserver.service
[Unit]
Description=netcat listener
After=network.target

[Service]
Restart=always
RestartSec=1
ExecStart=/usr/bin/bash -c '/usr/bin/nc -n -v -l -k -p 1313 >> /opt/data/$(hostname)-$(date -u +%%y%%m%%d-%%H).txt'

[Install]
WantedBy=multi-user.target

simple listener - receives text via raw tcp, sends into the file (restarts by cron once a day to generate new file)

I want to append current timestamp to each row of text coming (at the beginning or the end of the row, doesnt matter). Tried sed, awk, but the problem is that i cannot evaluate date for each row - it evaluates only once, when service started. Looks like this

109582 ?        Ss     0:00 /usr/bin/bash -c /usr/bin/nc -n -v -l -k -p 1313 | /usr/bin/sed 's/^/'$(date +%s)
 109583 ?        S      0:00 /usr/bin/nc -n -v -l -k -p 1313
 109584 ?        S      0:00 /usr/bin/sed s/^/1617555467\;/g

Pipe may be not the answer at all, but i'm kinda limited by bash. Any ideas?..