Read timeout connecting to server on Docker container - docker

Question

I'm trying to connect to a DB/2 container (image: ibmcom/db2) but it gives me a read timeout error. The host OS is Windows 10. I can see the port (50000) in the Windows PowerShell prompt, but it gives me a read timeout.
I've added an inbound Windows Defender rule to allow all local ports and an output rule to allow all remote ports. I have this regardless of the program. I realize this is not a good practice, but I'm trying to rule out a firewall issue. Despite this, it still gives me a read timeout error. I added more specific rules earlier, but they naturally did not help.
I also started an SSH server in that container and could log into it from within the container, but not outside of it. When connecting from outside, I got the same read timeout message. I do not feel this is a db2 issue.
Having said that, I was able to get sickp/alpine-sshd:7.5-r2 and gists/lighttpd to come start and be accessible from the host. That is, I can see the web default web page for lighttpd and log into the SSHD server for alpine-sshd. Both of these work with no appreciable delay. This worked before making the above firewall adjustments.
I'm convinced that somehow, this container is not working for me. Other people have tried the exact same docker run that I provide below, and it comes up for them.
I'm using Win 10, WSL2. Docker version 20.10.7, build f0df350.
I start the container by doing:
docker run -itd --name mydb-db2 \
--privileged=true \
-p 50000:50000 \
-e LICENSE=accept \
-e B2INSTANCE=db2inst1 \
-e DB2INST1_PASSWORD=<mypassword> \
-e DBNAME=MYDB \
-e TO_CREATE_SAMPLEDB=false \
-v db2:/database \
ibmcom/db2
Netstat evidence:
C:\Software>netstat /a /n |grep 50000
TCP 0.0.0.0:50000 0.0.0.0:0 LISTENING
TCP [::]:50000 [::]:0 LISTENING
Attempt to connect to jdbc:db2://localhost:50000/MYDB
on host system results in "Read timed out. ERRORCODE=-4499, SQLSTATE=08001"
Docker container status:
~/projects-new/db2$ docker container ls
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS
NAMES
110aa19976dd ibmcom/db2 "/var/db2_setup/lib/…" 2 days ago Up 28 minutes 22/tcp, 55000/tcp, 60006-60007/tcp, 0.0.0.0:50000->50000/tcp, :::50000->50000/tcp mydb-db2
Inspection of container:
~/projects-new/db2$ docker container inspect 110aa
[
{
"Id": "110aa19976ddb53d16eac9376476f974fee8e9c699da3f76c1e2e13c444655c2",
"Created": "2021-07-16T04:10:51.1247765Z",
"Path": "/var/db2_setup/lib/setup_db2_instance.sh",
"Args": [],
"State": {
"Status": "running",
"Running": true,
"Paused": false,
"Restarting": false,
"OOMKilled": false,
"Dead": false,
"Pid": 5459,
"ExitCode": 0,
"Error": "",
"StartedAt": "2021-07-18T03:56:45.0493495Z",
"FinishedAt": "2021-07-18T03:54:18.4239523Z"
},
"Image": "sha256:a6a5ee354fb1242a75d508982041cd48883f3fe7c9c9b485be0da6c0ebd44a39",
"ResolvConfPath": "/var/lib/docker/containers/110aa19976ddb53d16eac9376476f974fee8e9c699da3f76c1e2e13c444655c2/resolv.conf",
"HostnamePath": "/var/lib/docker/containers/110aa19976ddb53d16eac9376476f974fee8e9c699da3f76c1e2e13c444655c2/hostname",
"HostsPath": "/var/lib/docker/containers/110aa19976ddb53d16eac9376476f974fee8e9c699da3f76c1e2e13c444655c2/hosts",
"LogPath": "/var/lib/docker/containers/110aa19976ddb53d16eac9376476f974fee8e9c699da3f76c1e2e13c444655c2/110aa19976ddb53d16eac9376476f974fee8e9c699da3f76c1e2e13c444655c2-json.log",
"Name": "/mydb-db2",
"RestartCount": 0,
"Driver": "overlay2",
"Platform": "linux",
"MountLabel": "",
"ProcessLabel": "",
"AppArmorProfile": "",
"ExecIDs": null,
"HostConfig": {
"Binds": [
"db2:/database"
],
"ContainerIDFile": "",
"LogConfig": {
"Type": "json-file",
"Config": {}
},
"NetworkMode": "default",
"PortBindings": {
"50000/tcp": [
{
"HostIp": "",
"HostPort": "50000"
}
]
},
"RestartPolicy": {
"Name": "no",
"MaximumRetryCount": 0
},
"AutoRemove": false,
"VolumeDriver": "",
"VolumesFrom": null,
"CapAdd": null,
"CapDrop": null,
"CgroupnsMode": "host",
"Dns": [],
"DnsOptions": [],
"DnsSearch": [],
"ExtraHosts": null,
"GroupAdd": null,
"IpcMode": "private",
"Cgroup": "",
"Links": null,
"OomScoreAdj": 0,
"PidMode": "",
"Privileged": true,
"PublishAllPorts": false,
"ReadonlyRootfs": false,
"SecurityOpt": [
"label=disable"
],
"UTSMode": "",
"UsernsMode": "",
"ShmSize": 67108864,
"Runtime": "runc",
"ConsoleSize": [
0,
0
],
"Isolation": "",
"CpuShares": 0,
"Memory": 0,
"NanoCpus": 0,
"CgroupParent": "",
"BlkioWeight": 0,
"BlkioWeightDevice": [],
"BlkioDeviceReadBps": null,
"BlkioDeviceWriteBps": null,
"BlkioDeviceReadIOps": null,
"BlkioDeviceWriteIOps": null,
"CpuPeriod": 0,
"CpuQuota": 0,
"CpuRealtimePeriod": 0,
"CpuRealtimeRuntime": 0,
"CpusetCpus": "",
"CpusetMems": "",
"Devices": [],
"DeviceCgroupRules": null,
"DeviceRequests": null,
"KernelMemory": 0,
"KernelMemoryTCP": 0,
"MemoryReservation": 0,
"MemorySwap": 0,
"MemorySwappiness": null,
"OomKillDisable": false,
"PidsLimit": null,
"Ulimits": null,
"CpuCount": 0,
"CpuPercent": 0,
"IOMaximumIOps": 0,
"IOMaximumBandwidth": 0,
"MaskedPaths": null,
"ReadonlyPaths": null
},
"GraphDriver": {
"Data": {
"LowerDir": "/var/lib/docker/overlay2/b6ecb6d5e949ab8e58d9238e34878a563a45f5045d57c684e5a08b6ec833ebb4-init/diff:/var/lib/docker/overlay2/6cf25bf1ac29315c3832316ef32b1cae8cf1ed6e71e4ddd9d08ab5566f81da9e/diff:/var/lib/docker/overlay2/76ca13571a6d253356b48ac20b408d33f80c5e6b429c132533e60c7578e99fb3/diff:/var/lib/docker/overlay2/e1a78196ef6f70929701e708904cb2696189c37a40839a0f20407148d2d90f1d/diff:/var/lib/docker/overlay2/efa2b4a3bc7e7411a671f05ad9121a4bb609452560b5f73d4b765e8519bfa36d/diff:/var/lib/docker/overlay2/933425814e17216adcfcac390e789c6dfc8ada12ded902db2ca9a542a5ff555c/diff:/var/lib/docker/overlay2/2ec2f25d859b77fd93a16468e40de569c41b35055c58277ad97d839cb33a01ac/diff:/var/lib/docker/overlay2/62aeaecc9fea67541671d95f691a2d8ddc9076ee0ae3bc96cd3b030a3ecc663b/diff:/var/lib/docker/overlay2/f04ce4e91dedc0c14073e43734ca252a7c0bd6f6ed9ab89f77d6797f72312f2d/diff:/var/lib/docker/overlay2/21b929e594040a64ffb0cd2c8bd4d3d7f630a3ec3dd79e8157c41c0d9783faa6/diff:/var/lib/docker/overlay2/c5e235fc2e9dc254394bcae472264b133530f5dfbb285cfe5f0ba0dac26ce4c4/diff:/var/lib/docker/overlay2/8f68a8bb1e9ca565aa1d8debc221bb498512a6ed24cc07bcf3ef07c8c42e045f/diff:/var/lib/docker/overlay2/745a0aa01d1a904ce08c22d07be527cdb39da0c37b87a66a57062cc307ca4d4c/diff:/var/lib/docker/overlay2/f0a873fda45d17a036833dd0dc9362f02b0ab00c590f23bf38ba59d06c624272/diff",
"MergedDir": "/var/lib/docker/overlay2/b6ecb6d5e949ab8e58d9238e34878a563a45f5045d57c684e5a08b6ec833ebb4/merged",
"UpperDir": "/var/lib/docker/overlay2/b6ecb6d5e949ab8e58d9238e34878a563a45f5045d57c684e5a08b6ec833ebb4/diff",
"WorkDir": "/var/lib/docker/overlay2/b6ecb6d5e949ab8e58d9238e34878a563a45f5045d57c684e5a08b6ec833ebb4/work"
},
"Name": "overlay2"
},
"Mounts": [
{
"Type": "volume",
"Name": "db2",
"Source": "/var/lib/docker/volumes/db2/_data",
"Destination": "/database",
"Driver": "local",
"Mode": "z",
"RW": true,
"Propagation": ""
},
{
"Type": "volume",
"Name": "47c06e44c75f70947a907a0972924536761f70f15971459e8be6015b29e2e48c",
"Source": "/var/lib/docker/volumes/47c06e44c75f70947a907a0972924536761f70f15971459e8be6015b29e2e48c/_data",
"Destination": "/hadr",
"Driver": "local",
"Mode": "",
"RW": true,
"Propagation": ""
}
],
"Config": {
"Hostname": "110aa19976dd",
"Domainname": "",
"User": "",
"AttachStdin": false,
"AttachStdout": false,
"AttachStderr": false,
"ExposedPorts": {
"22/tcp": {},
"50000/tcp": {},
"55000/tcp": {},
"60006/tcp": {},
"60007/tcp": {}
},
"Tty": true,
"OpenStdin": true,
"StdinOnce": false,
"Env": [
"LICENSE=accept",
"B2INSTANCE=db2inst1",
"DB2INST1_PASSWORD=<mypassword>",
"DBNAME=BLUECOST",
"TO_CREATE_SAMPLEDB=false",
"PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin",
"container=oci",
"STORAGE_DIR=/database",
"HADR_SHARED_DIR=/hadr",
"DBPORT=50000",
"TSPORT=55000",
"SETUPDIR=/var/db2_setup",
"SETUPAREA=/tmp/setup",
"NOTVISIBLE=in users profile",
"LICENSE_NAME=db2dec.lic"
],
"Cmd": null,
"Image": "ibmcom/db2",
"Volumes": {
"/database": {},
"/hadr": {}
},
"WorkingDir": "",
"Entrypoint": [
"/var/db2_setup/lib/setup_db2_instance.sh"
],
"OnBuild": null,
"Labels": {
"architecture": "x86_64",
"build-date": "2021-06-01T05:31:45.840349",
"com.redhat.build-host": "cpt-1007.osbs.prod.upshift.rdu2.redhat.com",
"com.redhat.component": "ubi7-container",
"com.redhat.license_terms": "https://www.redhat.com/en/about/red-hat-end-user-license-agreements#UBI",
"description": "The Universal Base Image is designed and engineered to be the base layer for all of your containerized applications, middleware and utilities. This base image is freely redistributable, but Red Hat only supports Red Hat technologies through subscriptions for Red Hat products. This image is maintained by Red Hat and updated regularly.",
"desktop.docker.io/wsl-distro": "Ubuntu-20.04",
"distribution-scope": "public",
"io.k8s.description": "The Universal Base Image is designed and engineered to be the base layer for all of your containerized applications, middleware and utilities. This base image is freely redistributable, but Red Hat only supports Red Hat technologies through subscriptions for Red Hat products. This image is maintained by Red Hat and updated regularly.",
"io.k8s.display-name": "Red Hat Universal Base Image 7",
"io.openshift.tags": "base rhel7",
"name": "ubi7",
"release": "405",
"summary": "Provides the latest release of the Red Hat Universal Base Image 7.",
"url": "https://access.redhat.com/containers/#/registry.access.redhat.com/ubi7/images/7.9-405",
"vcs-ref": "a4e710a688a6374670ecdd56637c3f683d11cbe3",
"vcs-type": "git",
"vendor": "Red Hat, Inc.",
"version": "7.9"
}
},
"NetworkSettings": {
"Bridge": "",
"SandboxID": "570856178f99951c7cdfccc638a3404f906a7a89905ba9d39181cd9310f4380b",
"HairpinMode": false,
"LinkLocalIPv6Address": "",
"LinkLocalIPv6PrefixLen": 0,
"Ports": {
"22/tcp": null,
"50000/tcp": [
{
"HostIp": "0.0.0.0",
"HostPort": "50000"
},
{
"HostIp": "::",
"HostPort": "50000"
}
],
"55000/tcp": null,
"60006/tcp": null,
"60007/tcp": null
},
"SandboxKey": "/var/run/docker/netns/570856178f99",
"SecondaryIPAddresses": null,
"SecondaryIPv6Addresses": null,
"EndpointID": "a50d8643af88c0d677a9dc2d889f20ab909f46707bb7bd0f8168666b18d1b414",
"Gateway": "172.17.0.1",
"GlobalIPv6Address": "",
"GlobalIPv6PrefixLen": 0,
"IPAddress": "172.17.0.2",
"IPPrefixLen": 16,
"IPv6Gateway": "",
"MacAddress": "02:42:ac:11:00:02",
"Networks": {
"bridge": {
"IPAMConfig": null,
"Links": null,
"Aliases": null,
"NetworkID": "408fe3a7130f9791810b8668b60b7f90478f4673f79270539044362e8c12d88f",
"EndpointID": "a50d8643af88c0d677a9dc2d889f20ab909f46707bb7bd0f8168666b18d1b414",
"Gateway": "172.17.0.1",
"IPAddress": "172.17.0.2",
"IPPrefixLen": 16,
"IPv6Gateway": "",
"GlobalIPv6Address": "",
"GlobalIPv6PrefixLen": 0,
"MacAddress": "02:42:ac:11:00:02",
"DriverOpts": null
}
}
}
}
]
I didn't see the db2 container listed. These are my networks:
C:\Software>docker network ls
NETWORK ID NAME DRIVER SCOPE
408fe3a7130f bridge bridge local
38fc17e8e6f1 cirrus-ssc-file-sender_default bridge local
1668ab71959f host host local
4bf4f6b3a57e minikube bridge local
e07fc0032414 none null local
Instead, I found it on the bridge network.
I'm not trying to do anything fancy. I'd really rather it run on the same network host. If the host system can "see" the exposed port of 50000 via Netstat, wouldn't that mean it's not a firewall issue?
Update: I turned off Windows Defender and it still does not work.
Update 2: I hosted the same container on a different machine but on my home network. When I try to connect to it from the problem machine, it gives me the same read timeout error. However, it works from the hosting machine. Somehow there seems to be a problem between this particular Windows machine and this particular container.
Update 3: SVCENAME info:
I ran the following inside the db2 container:
$su db2inst1 (when I log in it goes to root)
$cd ~
$. ./.bashrc
$db2 get dbm cfg |grep SVCENAME
TCP/IP Service name (SVCENAME) = db2c_db2inst1
SSL service name (SSL_SVCENAME) =
$grep dbc2_db2inst1 /etc/services
db2c_db2inst1 50000/tcp
db2c_db2inst1_ssl 50001/tcp
DB2 Container OS Version info:
$ cat /etc/*release
NAME="Red Hat Enterprise Linux Server"
VERSION="7.9 (Maipo)"
ID="rhel"
ID_LIKE="fedora"
VARIANT="Server"
VARIANT_ID="server"
VERSION_ID="7.9"
PRETTY_NAME="Red Hat Enterprise Linux Server 7.9 (Maipo)"
ANSI_COLOR="0;31"
CPE_NAME="cpe:/o:redhat:enterprise_linux:7.9:GA:server"
HOME_URL="https://www.redhat.com/"
BUG_REPORT_URL="https://bugzilla.redhat.com/"
REDHAT_BUGZILLA_PRODUCT="Red Hat Enterprise Linux 7"
REDHAT_BUGZILLA_PRODUCT_VERSION=7.9
REDHAT_SUPPORT_PRODUCT="Red Hat Enterprise Linux"
REDHAT_SUPPORT_PRODUCT_VERSION="7.9"
Red Hat Enterprise Linux Server release 7.9 (Maipo)
Red Hat Enterprise Linux Server release 7.9 (Maipo)
WSL Linux version used:
$ cat /etc/*release
DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=20.04
DISTRIB_CODENAME=focal
DISTRIB_DESCRIPTION="Ubuntu 20.04.1 LTS"
NAME="Ubuntu"
VERSION="20.04.1 LTS (Focal Fossa)"
ID=ubuntu
ID_LIKE=debian
PRETTY_NAME="Ubuntu 20.04.1 LTS"
VERSION_ID="20.04"
HOME_URL="https://www.ubuntu.com/"
SUPPORT_URL="https://help.ubuntu.com/"
BUG_REPORT_URL="https://bugs.launchpad.net/ubuntu/"
PRIVACY_POLICY_URL="https://www.ubuntu.com/legal/terms-and-policies/privacy-policy"
VERSION_CODENAME=focal
UBUNTU_CODENAME=focal
Windows version info of the host system (from winver):
Windows 10
Version 21H1 (OS Build 19043.1110)
Computer successfully connecting to DB/2 container:
$ cat /etc/*release
Fedora release 30 (Thirty)
NAME=Fedora
VERSION="30 (Workstation Edition)"
ID=fedora
VERSION_ID=30
VERSION_CODENAME=""
PLATFORM_ID="platform:f30"
PRETTY_NAME="Fedora 30 (Workstation Edition)"
ANSI_COLOR="0;34"
LOGO=fedora-logo-icon
CPE_NAME="cpe:/o:fedoraproject:fedora:30"
HOME_URL="https://fedoraproject.org/"
DOCUMENTATION_URL="https://docs.fedoraproject.org/en-US/fedora/f30/system-administrators-guide/"
SUPPORT_URL="https://fedoraproject.org/wiki/Communicating_and_getting_help"
BUG_REPORT_URL="https://bugzilla.redhat.com/"
REDHAT_BUGZILLA_PRODUCT="Fedora"
REDHAT_BUGZILLA_PRODUCT_VERSION=30
REDHAT_SUPPORT_PRODUCT="Fedora"
REDHAT_SUPPORT_PRODUCT_VERSION=30
PRIVACY_POLICY_URL="https://fedoraproject.org/wiki/Legal:PrivacyPolicy"
VARIANT="Workstation Edition"
VARIANT_ID=workstation
Fedora release 30 (Thirty)
Fedora release 30 (Thirty)

Answer 1

Your symptom might be caused by some machine specific configuration, or some downlevel component (in particular WSL2).
On my hardware, at the current date, with current version of WSL2, ibmcom/db2 accepts connections from the local MS-Windows host (via jdbc ) with the following mix of components:
MS-Windows 10 Pro build 19043 (21H1) x64
the latest build of the "Linux WSL2 kernel package for x64 machines"
Docker Desktop 3.5.2 configured to use WSL2
However, with a previous mix of configurations , I recreated your failure symptom with WSL2, i.e. jdbc connection attempt from local MSWindows host into the linux container gave sqlcode -4499 (in my case reply.fill() insufficient data).
The failing combination was:
MS-Windows 10 Pro build 19041 x64.
older build of "Linux WSL2 kernel package for x64 machines" (downloaded before 22/July/2021)
Docker Desktop 3.5.2 configured for WSL2
With the previous failing combination, only WSL2 back end recreated your symptom, but the Hyper-V back end worked correctly.
With Docker-Desktop on a Win10PRO environment, right click on its icon, choose Settings, and it lets you tick (or untick) "Use WSL2 based engine", click Apply and Restart. You may get other notifications. You may lose your containers and images and need to download them again so if you need to preserve any data then arrange that separately before changing the back end.
If you cannot make progress via upgrading components, then a re-install or image may be an option.