IPv6 - Server not reachable

ger64

ger64

Verified User
Joined
Apr 18, 2017
Messages
29
Hello,
Sorry for my bad english.

Contabo Cloud VPS
DirectAdmin: 1.705
AlmaLinux9
ConfigServer+lfd
Fresh Install DirectAdmin at Fresh 8Gb RAM server, 4 core.
2 Test domains: 100% internet.nl score.

After reboot I get message: The service lfd on server xxx.xxx.nl is currently down

When i make fresh install (or later reboot):
  1. The first +/- 30-60 minutes: Tests at:
    1. Internet.nl:
      1. IPv4 = 100%
      2. IPV6 = 100%
    2. ssllabs.com:
      1. IPv4 = A+
      2. IPv6 = A+
  2. After 30-60 minutes and later (days): Tests at:
    1. Internet.nl:
      1. IPv4 = 100%
      2. IPV6 = Unable to connect to the server
    2. ssllabs.com:
      1. IPv4 = A+
      2. IPv6 = Unable to connect to the server
  3. When I reboot the server:
    1. The same results from above (30-60 minutes, no problem. Later again IPv6: Unable to connect to the server
When I turn OFF ConfigServer+lfd (in Test Mode) en restart (but NOT reboot):
  1. At the direct moment (no delay) The same results as above.
    1. IPv6 = 100%
  2. 30-60 minutes later:
    1. IPv6 = Unable to connect to the server
When I turn OFF ConfigServer+lfd (so in Test Mode) en restart (AND reboot):
  1. At the direct moment (no delay) The same results as above.
    1. IPv6 = 100%
  2. 30-60 minutes later:
    1. IPv6 = Unable to connect to the server
Can anyone help me - Is it the Server (Contabo Cloud), The CSF or LFD?
Thanks ...
 
Last edited:
First 30-60 minutes (with reboot) (the green lines = after reboot)
 

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Hello,

Do you happen to use DHCP? You might stop using DCHP in favour of a fixed IP setup. Search internet on how to complete the setup.
 
Thanks for your reply:
I don't understand (You might stop using DCHP in favour of a fixed IP setup), This server is one of many servers I had and I had never problems with installations and tests. Alway 100% and A+ A+. Just basic setup at first and immidiately tests a domain afther a SSL Certificate, with result 100%. But 30-60 minutes later .... trouble.
 
That's my guess about DHCP. No other reasons come to my mind. Use nmcli to check the things.

If you don't know how to use nmcli and change to a fixed setup, you might contact Contabo support or even DirectAdmin support on the matter, or hire a 3rd party (which I am as well as some other guys here).
 
ger64 said:
When I turn OFF ConfigServer+lfd (so in Test Mode) en restart (AND reboot):
Click to expand...
Looks like it's happening every time.
So if you turn off configserver so it will nog run, can you ping the ipv6?

It might be a Contabo issue, we had once too that we didn't even get ipv6 to work on Alma 9 before installing by the command they provided.
Normally it's no issue but this might not be a DA issue.

Have you tried using SSH to the server using ipv6? And also try to ping the ipv6?
So this way if it's reachable and you can connect to it, with CSF/LFD disabled and no other firewall (like firewalld) active?
If then also not being able to connect it might also be a Contabo issue.

Another way is not to only have DA provide the ipv6 but to also put the ipv6 in the startup script of the OS same like the ipv4.
So that even if DA is not present, the ipv6 should be present same like the ipv4.
 
Richard thanks for the answer. Trying al lot of things now, to see. Problem is: I have to wait each time 60 minutes to (some times 3 hours) to see if it's stable. ... Thanks. Each time everything the first 60 minutes 100% score. But sometimes after 3 hours 61% score because IPv6 not reachable.

At this moment I made a re-install (SnapShot first DirectAdmin) and try VirtualMin with SSL Certificate. So I have to wait again some hours to see where is goes wrong ...
:)

To be continues ...
 
Last edited:
VirtualMin (new install) at new Almalinux with same website and automatic SSL LetsEncryot, at internet.nl ans ssllabs.com - first 30 minutes: 100% eveything. After 30 minutes: 61% score and IPv6 not reachable.
Output from Startup OS:

AUTOCONNECT_PRIORITY=120
BOOTPROTO=none
DEFROUTE=yes
DEVICE=eth0
GATEWAY=169.58.0.1
HWADDR=00:50:56:65:f4:86
IPADDR=169.58.XX.XXX
IPV6ADDR=2a02:c207:2346:XXXX:0000:0000:0000:0001/64
IPV6INIT=yes
IPV6_AUTOCONF=no
IPV6_DEFAULTGW=fe80::1
IPV6_FORCE_ACCEPT_RA=no
NETMASK=255.255.128.0
ONBOOT=yes
TYPE=Ethernet
USERCTL=no

Searching more: To be continued ....
 
I have made a Ticket to Contabo with:
“IPv6 service to my server becomes unreachable after ~60 minutes. AAAA stays the same (2a02:c207:xxxx:xxxx::1). I see 100% packet loss (ICMP) and HTTP/HTTPS on IPv6 time out from outside. IPv4 (169.58.xx.xxxx) remains reachable. Server-side firewall (CSF/LFD) disabled and issue persists. Please check IPv6 upstream routing/filters for this instance and whether any IPv6 edge device/ACL causes periodic drops.”
 
from my experience, in the past, contabo is very bad service, I recommended to find other provider.

see in reddit about contabo reviews
 
Ohm J said:
from my experience, in the past, contabo is very bad service, I recommended to find other provider.

see in reddit about contabo reviews
Click to expand...
Thanks, I know. I read the trustpilot reviews always. But I have years long Contabo (simple) servers, and never had issues, until the last (cloud) server.
 
ger64 said:
When ConfigServer is OFF. The same results (after 30 minutes).
Click to expand...
Looks to me it's a Contabo issue in this case, normally this can not happen. I suggest contacting their support and say you loose your ipv6 after half an hour. They have to check it, this is not a DA problem as far as I can see.

Contabo has great prices but is also for overselling. You can get lucky, we only have a dns vps there. But they also do a overselling which makes your vps slower.
Have a look at Hetzner Cloud VPS maybe as alternative if they can not fix the issue for you.
 
Richard
Richard G said:
Looks to me it's a Contabo issue in this case, normally this can not happen. I suggest contacting their support and say you loose your ipv6 after half an hour. They have to check it, this is not a DA problem as far as I can see.

Contabo has great prices but is also for overselling. You can get lucky, we only have a dns vps there. But they also do a overselling which makes your vps slower.
Have a look at Hetzner Cloud VPS maybe as alternative if they can not fix the issue for you.
Click to expand...
Thanks Richard
 
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