I know that this has been posted before, but there appears to be no satisfactory list of steps to solve it. I had this working on my old OMV4 setup - but it crashed and I am unable to remember how to do it.
Environment:
- OMV 4.1.8 installed on Dell PE R720
- Docker-UI plugin and Docker installed via OMV UI of the same version
- Docker Client v18.03.1-ce
- Docker Server v18.03.1-ce
- OMV says I have all the latest patches
- No Docker network changes to default setting
Scenario #1:
- Pull linuxserver/tt-rss:latest image
- Pull postgres:9 image
- Run Postgres image as "postgres9" on Bridge network with either no ports exposed, or 5432->5432
- Run TTRSS image as "ttrss" on Bridge network with all the appropriate ports exposed and the extra arguments "--link postgres9:db"
- TTRSS web application is unable to connect to the Postgres9 database. I receive the following error: "Unable to connect to database (as ttrss to postgres9, database ttrss):Unable to connect to database (as ttrss to postgres9, database ttrss):"
- I run an interactive terminal on ttrss (docker exec -it ttrss bash) and not only can I ping the IP Address which postgres9 is using, if I ping via the name "postgres9" it resolves properly.
Scenario #2:.
- Pull linuxserver/tautulli (formerly PlexPy)
- Run Tautulli as "plexpy" on Bridge network with proper ports exposed
- Access the exported port on my OMV server (172.17.0.2:8181 exposed as 8181)
- The first step is for Tautulli to connect to Plex.TV and collect a token
- Web application attempts to fetch token ... but fails with the following error:
2018-06-12 22:50:32 - INFO :: CP Server Thread-7 : Tautulli PlexTV :: Fetching a new Plex.tv token for Tautulli.
2018-06-12 22:50:52 - WARNING :: CP Server Thread-7 : Failed to access uri endpoint /users/sign_in.xml. Is your server maybe accepting SSL connections only? HTTPSConnectionPool(host='plex.tv', port=443): Max retries exceeded with url: /users/sign_in.xml (Caused by NewConnectionError('<urllib3.connection.VerifiedHTTPSConnection object at 0x7f4b0635d450>: Failed to establish a new connection: [Errno -3] Try again',))
The reason I posted two different scenarios is that I believe the problems are linked. I seem to remember that on an earlier version of Docker (before they went to a CE release) on OMV3 (yes, I inline upgraded to OMV4), there was a command or configuration I needed to change to allow containers on the default docker0 bridge to a) be able to talk to each other even with the "--link" argument and b) to NAT through the host OMV server to the outside world.
I've tried to look at the easy thing:
root@server:~# cat /proc/sys/net/ipv4/ip_forward
1
root@server:~# iptables -L
Chain INPUT (policy ACCEPT)
target prot opt source destination
ACCEPT all -- 192.168.2.0/24 anywhere
ACCEPT all -- anywhere anywhere
Chain FORWARD (policy DROP)
target prot opt source destination
DOCKER-USER all -- anywhere anywhere
DOCKER-ISOLATION-STAGE-1 all -- anywhere anywhere
ACCEPT all -- anywhere anywhere ctstate RELATED,ESTABLISHED
DOCKER all -- anywhere anywhere
ACCEPT all -- anywhere anywhere
ACCEPT all -- anywhere anywhere
Chain OUTPUT (policy ACCEPT)
target prot opt source destination
Chain DOCKER (1 references)
target prot opt source destination
ACCEPT tcp -- anywhere 172.17.0.2 tcp dpt:8181
ACCEPT tcp -- anywhere 172.17.0.7 tcp dpt:postgresql
ACCEPT tcp -- anywhere 172.17.0.10 tcp dpt:https
ACCEPT tcp -- anywhere 172.17.0.10 tcp dpt:http
Chain DOCKER-ISOLATION-STAGE-1 (1 references)
target prot opt source destination
DOCKER-ISOLATION-STAGE-2 all -- anywhere anywhere
RETURN all -- anywhere anywhere
Chain DOCKER-ISOLATION-STAGE-2 (1 references)
target prot opt source destination
DROP all -- anywhere anywhere
RETURN all -- anywhere anywhere
Chain DOCKER-USER (1 references)
target prot opt source destination
RETURN all -- anywhere anywhere
Alles anzeigen
Is there anything I have overlooked?
Would any additional information help in finding the root of the issue?
Many thanks in advance! Logically Yours,
--rogue