Polkadot/Parity v0.9.3 docker container dies with resolv.config parse error

[vishgpt]

Hi Team,

I am trying to setup polkadot node and following the exact instructions given in this documentation. But my node does not work and docker container gets stopped with below mentioned error:

Error:
0: IO Error
1: Error parsing resolv.conf: InvalidOption(3)

Steps that i have executed on Ubuntu 18.04 version:
docker run -d -p 30333:30333 -p 9933:9933 -v /my/local/folder:/polkadot parity/polkadot:latest --chain polkadot --rpc-external --rpc-cors all

Logs:
2021-06-15 13:20:23 Parity Polkadot
2021-06-15 13:20:23 ✌️ version 0.9.3-aa3867609-x86_64-linux-gnu
2021-06-15 13:20:23 ❤️ by Parity Technologies admin@parity.io, 2017-2021
2021-06-15 13:20:23 📋 Chain specification: Polkadot
2021-06-15 13:20:23 🏷 Node name: sore-kitten-4526
2021-06-15 13:20:23 👤 Role: FULL
2021-06-15 13:20:23 💾 Database: RocksDb at /polkadot/.local/share/polkadot/chains/polkadot/db
2021-06-15 13:20:23 ⛓ Native runtime: polkadot-9030 (parity-polkadot-0.tx7.au0)
Error:
0: IO Error
1: Error parsing resolv.conf: InvalidOption(3)

Location:
src/main.rs:25

━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ BACKTRACE ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
1: __libc_start_main
at :

Run with COLORBT_SHOW_HIDDEN=1 environment variable to disable frame filtering.
Run with RUST_BACKTRACE=full to include source snippets.

Any help would be greatly appreciated.

[vishgpt]

@freiit: Any help would be highly appreciated

[bkchr]

CC @s3krit

[arturgontijo]

I've got a Permission Denied error instead of the resolv.conf one...
I was able to fix it by running the container as root (-u 0):

docker run --name POLKADOT_NODE -d -p 30333:30333 -p 9933:9933 -u 0 -v /tmp/polkadot:/root/.local/share/polkadot/ parity/polkadot:latest --chain polkadot --rpc-external --rpc-cors all

Maybe that would also fix your issue @vishgpt

[arturgontijo]

Another approach would be using host network (no need to expose ports):

docker run \
  --name POLKADOT_NODE \
  --network host \
  -v /tmp/polkadot:/root/.local/share/polkadot/ \
  -d parity/polkadot:latest --chain polkadot --rpc-external --rpc-cors all

[vishgpt]

I tried both above options given but still facing the same issue. Any other suggestions?

[arturgontijo]

@vishgpt looks like you have some issue with your host /etc/resolv.conf.

Are you able to run any other Docker image?

docker run \
  --name UBUNTU_20_04 \
  -ti ubuntu:20.04 bash

Then, inside the container, run:

apt update

Just to check if it's able to resolve the apt source server names.

[vishgpt]

@arturgontijo Yes, i am able to run many other docker images. I am using Ubuntu 18.04... does that seem to be a problem?

[freiit]

I tried to reproduce by reducing complexity.

I called

docker pull parity/polkadot:latest
docker run -ti parity/polkadot:latest --chain polkadot --rpc-external --rpc-cors all

and my output does not produce any error:

2021-06-17 03:58:28  Parity Polkadot 
2021-06-17 03:58:28  ✌️  version 0.9.3-aa3867609-x86_64-linux-gnu    
2021-06-17 03:58:28  ❤️  by Parity Technologies <admin@parity.io>, 2017-2021    
2021-06-17 03:58:28  📋 Chain specification: Polkadot    
2021-06-17 03:58:28  🏷 Node name: decisive-paste-6777    
2021-06-17 03:58:28  👤 Role: FULL    
2021-06-17 03:58:28  💾 Database: RocksDb at /polkadot/.local/share/polkadot/chains/polkadot/db    
2021-06-17 03:58:28  ⛓  Native runtime: polkadot-9030 (parity-polkadot-0.tx7.au0)    
2021-06-17 03:58:29  🔨 Initializing Genesis block/state (state: 0x29d0…4e17, header-hash: 0x91b1…90c3)    
2021-06-17 03:58:29  👴 Loading GRANDPA authority set from genesis on what appears to be first startup.    
2021-06-17 03:58:30  ⏱  Loaded block-time = 6s from block 0x91b171bb158e2d3848fa23a9f1c25182fb8e20313b2c1eb49219da7a70ce90c3    

I assume the error message you got shows the real issue already:

1: Error parsing resolv.conf: InvalidOption(3)

What is in your resolv.conf?

[vishgpt]

Below is my resolv.conf:

This file is being maintained by Puppet.

DO NOT EDIT

search us.deloitte.com
options timeout:5 retries:2
nameserver 10.152.0.110
nameserver 10.152.0.111

[freiit]

You need to put your file in a code block, otherwise the control characters (like #) interfere with markdown from Github.

Beside that - error code says InvalidOption - maybe that line "options" does not make any sense. This file is not part of the docker container installation and I can't help you with this.

Maybe delete or edit that file? Its in your local system, not in the docker container, so you generated or copied it from somewhere? Again - can't help you with this.