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Common operations at DCLIPv6OnlyHosting » History » Revision 4

Revision 3 (ll nu, 03/10/2020 06:16 PM) → Revision 4/5 (ll nu, 03/10/2020 06:17 PM)

h1. Common operations at DCLIPv6OnlyHosting 

 {{toc}} 

 h2. How to check if a customer VM is alive? 

 There are many ways to check if a DCL VM is running/reachable. Here's the standard workflow: 

 * First check: try to 'ping' the VM to see if it is up and reachable from the global Internet. 
 ** IPv6: @ping -6 $IPV6_ADDR@ and (if available) IPv4: @ping -4 $IPV4_ADDR@ 
 ** The VM is up and running if you get an answer, *but* ICMP requests (= ping) might be blocked by a firewall on the target or the target's networking might be broken: you'll have to switch to the next check. 
 * Second check: find the VM on "OpenNebula SunStone":https://opennebula.ungleich.ch (= OpenNebula Web interface) under _the Instances > VM_ tab and check its _LCM State_, which should be @RUNNING@ if everything's alright. Try to open the VNC display (top-left VNC button once you have selected the VM) to see what's currently on screen (likely TTY login, which means the VM is up but does not say anything on networking). 
 ** If state is not @RUNNING@ and VNC is unavailable/does not show anything, assume VM is down/blocked and requires (re)boot. 
 * If the VM is up but does not answer to ICMP requests (= ping), try to see if there is any other open port with @nmap@. 
 ** @nmap -6 $IPV6_ADDR@ (might take some time) will try to find open ports on the target. Try IPv6 and IPv4 (replace @-6@ by @-4@) if available, since some software/firewall default to IPv4-only. See the example below for a healthy service. 
 *** You can try to SSH if available, or to curl HTTP(S) ports (@curl http://$ADDR@). 
 ** If @ping@ does not work and @nmap@ does not return anything, assume network is broken. 

 h3. NMAP example 

 <pre> 
 I ~ » nmap -6 redmine.ungleich.ch 
 Starting Nmap 7.80 ( https://nmap.org ) at 2020-02-24 11:16 CET 
 Nmap scan report for redmine.ungleich.ch (2a0a:e5c0:0:2:400:b3ff:fe39:7ba3) 
 Host is up (0.048s latency). 
 Other addresses for redmine.ungleich.ch (not scanned): 185.203.112.9 
 rDNS record for 2a0a:e5c0:0:2:400:b3ff:fe39:7ba3: 2a0a-e5c0-0000-0002-0400-b3ff-fe39-7ba3.loves.ipv6.at.ungleich.ch 
 Not shown: 996 closed ports 
 PORT      STATE SERVICE 
 22/tcp    open    ssh 
 25/tcp    open    smtp 
 80/tcp    open    http 
 443/tcp open    https 

 Nmap done: 1 IP address (1 host up) scanned in 13.58 seconds 
 </pre> 


 "Similar wikipage":https://redmine.ungleich.ch/projects/datacenterlight/wiki/Support_customer's_requests [[https://redmine.ungleich.ch/projects/datacenterlight/wiki/Support_customer's_requests]]