# Trying to connect to an Oracle data source **URL:** \ **Category:** Matillion ETL\ **Created:** [April 28, 2021, 12:51pm UTC](https://matillioncommunity.discourse.group/t/trying-to-connect-to-an-oracle-data-source/1324 "2021-04-28T12:51:56Z")\ **Posts on this page:** 17\ **Page:** 1
**Author:** ![DF214566](https://avatars.discourse-cdn.com/v4/letter/d/ecd19e/32.png) [@DF214566](https://matillioncommunity.discourse.group/u/DF214566)\ **Post date:** [April 28, 2021, 12:51pm UTC](https://matillioncommunity.discourse.group/t/trying-to-connect-to-an-oracle-data-source/1324/1 "2021-04-28T12:51:56Z")
I'm trying to connect to an Oracle data source but get 'IO Error: The Network Adapter could not establish the connection'. What could be the reason for this message? ---
**Author:** ![Bryan](https://avatars.discourse-cdn.com/v4/letter/b/db5fbb/32.png) [@Bryan](https://matillioncommunity.discourse.group/u/Bryan)\ **Post date:** [April 30, 2021, 2:51pm UTC](https://matillioncommunity.discourse.group/t/trying-to-connect-to-an-oracle-data-source/1324/2 "2021-04-30T14:51:59Z")
HI [@DF214566](https://matillioncommunity.discourse.group/u/DF214566)​, I fully admit that I am not an Oracle guy at all. So, I will throw out some ideas since it doesn't seem to be an Oracle specific issue. The first couple things I would check is make sure that the Matillion instance can get to and has access to the Oracle data source. With firewalling and routing it's sometimes not clear if that connection is possible. You can test that Matillion has access to the Oracle data source by SSH'ing into the Matillion instance. Once on the console, try to ping the Oracle source server. If that is successful then you at least know that you can get to the data source. If you wanted to get real precise, you could install telnet on the Matillion instance and try connecting to the IP and port on the Oracle server that the database connection is supposed to be open. Since the error is a Network IO error, I really don't suspect it to be a permissions issue. If you find that the Matillion instance should be able to connect to Oracle from a network perspective I would then concentrate on the connection string you are using. I hope this helps in some way. ---
**Author:** ![IM050974](https://avatars.discourse-cdn.com/v4/letter/i/e79b87/32.png) [@IM050974](https://matillioncommunity.discourse.group/u/IM050974)\ **Post date:** [October 25, 2022, 1:52pm UTC](https://matillioncommunity.discourse.group/t/trying-to-connect-to-an-oracle-data-source/1324/3 "2022-10-25T13:52:06Z")
![0694G00000OGjFQQA1_0D74G000008hDt2SAE](https://us1.discourse-cdn.com/flex002/uploads/matillioncommunity/original/1X/bcfc921e476673f174810b1b8444ffec5eed02a7.png) ---
**Author:** ![IM050974](https://avatars.discourse-cdn.com/v4/letter/i/e79b87/32.png) [@IM050974](https://matillioncommunity.discourse.group/u/IM050974)\ **Post date:** [November 7, 2021, 3:55pm UTC](https://matillioncommunity.discourse.group/t/trying-to-connect-to-an-oracle-data-source/1324/4 "2021-11-07T15:55:58Z")
Were you able to solve this problem ? If yes please share, I am experiencing the same problem and I am not sure how to resolve it.  ---
**Author:** ![Tinju](https://avatars.discourse-cdn.com/v4/letter/t/e19b73/32.png) [@Tinju](https://matillioncommunity.discourse.group/u/Tinju)\ **Post date:** [September 21, 2022, 1:34am UTC](https://matillioncommunity.discourse.group/t/trying-to-connect-to-an-oracle-data-source/1324/5 "2022-09-21T01:34:29Z")
Hi [@IM050974](https://matillioncommunity.discourse.group/u/IM050974) (Customer)​ , Have you found the solution to resolve this issue? ---
**Author:** ![IM050974](https://avatars.discourse-cdn.com/v4/letter/i/e79b87/32.png) [@IM050974](https://matillioncommunity.discourse.group/u/IM050974)\ **Post date:** [September 26, 2022, 6:04am UTC](https://matillioncommunity.discourse.group/t/trying-to-connect-to-an-oracle-data-source/1324/6 "2022-09-26T06:04:45Z")
Yes, i was able to solve the problem. i had to build oracle connection string. ---
**Author:** ![Sri](https://avatars.discourse-cdn.com/v4/letter/s/e9a140/32.png) [@Sri](https://matillioncommunity.discourse.group/u/Sri)\ **Post date:** [October 25, 2022, 1:47pm UTC](https://matillioncommunity.discourse.group/t/trying-to-connect-to-an-oracle-data-source/1324/7 "2022-10-25T13:47:38Z")
Hi,   Can you share the format of the connecting you've built?   Thanks, Sri ---
**Author:** ![IM050974](https://avatars.discourse-cdn.com/v4/letter/i/e79b87/32.png) [@IM050974](https://matillioncommunity.discourse.group/u/IM050974)\ **Post date:** [October 25, 2022, 1:54pm UTC](https://matillioncommunity.discourse.group/t/trying-to-connect-to-an-oracle-data-source/1324/8 "2022-10-25T13:54:29Z")
i greyed out servername and db name but that is the string you need if you are able to see database instance on cloud. ---
**Author:** ![Sri](https://avatars.discourse-cdn.com/v4/letter/s/e9a140/32.png) [@Sri](https://matillioncommunity.discourse.group/u/Sri)\ **Post date:** [October 25, 2022, 1:57pm UTC](https://matillioncommunity.discourse.group/t/trying-to-connect-to-an-oracle-data-source/1324/9 "2022-10-25T13:57:04Z")
Thanks. That is exactly How I'm using it but still running into issues. Are you using Host name or Host IP in the connecting string?   Thanks, Sri ---
**Author:** ![IM050974](https://avatars.discourse-cdn.com/v4/letter/i/e79b87/32.png) [@IM050974](https://matillioncommunity.discourse.group/u/IM050974)\ **Post date:** [October 25, 2022, 1:58pm UTC](https://matillioncommunity.discourse.group/t/trying-to-connect-to-an-oracle-data-source/1324/10 "2022-10-25T13:58:53Z")
host Ip works for me. ---
**Author:** ![jubith.kariyath](https://sea2.discourse-cdn.com/flex002/user_avatar/matillioncommunity.discourse.group/jubith.kariyath/32/967_2.png) [@jubith.kariyath](https://matillioncommunity.discourse.group/u/jubith.kariyath)\ **Post date:** [October 26, 2022, 2:26pm UTC](https://matillioncommunity.discourse.group/t/trying-to-connect-to-an-oracle-data-source/1324/11 "2022-10-26T14:26:17Z")
is this resolved? I am facing the same error now. ---
**Author:** ![Sri](https://avatars.discourse-cdn.com/v4/letter/s/e9a140/32.png) [@Sri](https://matillioncommunity.discourse.group/u/Sri)\ **Post date:** [October 26, 2022, 2:32pm UTC](https://matillioncommunity.discourse.group/t/trying-to-connect-to-an-oracle-data-source/1324/12 "2022-10-26T14:32:30Z")
Not yet. Still working with Network engineers to troubleshoot the issue.   Try doing this- [How To: Check connectivity to remote sources (matillion.com)](https://support.matillion.com/s/article/How-To-Check-connectivity-to-remote-sources) to see if Matillion NetworkID/ Subnet mask is able to access your Oracle.   Thanks, Sri ---
**Author:** ![jubith.kariyath](https://sea2.discourse-cdn.com/flex002/user_avatar/matillioncommunity.discourse.group/jubith.kariyath/32/967_2.png) [@jubith.kariyath](https://matillioncommunity.discourse.group/u/jubith.kariyath)\ **Post date:** [October 26, 2022, 2:44pm UTC](https://matillioncommunity.discourse.group/t/trying-to-connect-to-an-oracle-data-source/1324/13 "2022-10-26T14:44:24Z")
it is strange! I have created a new instance of matillion and the error is encountered; whereas it works smooth on the old instance.   also, the new instance is created by restoring the backup of the old one !! ---
**Author:** ![Sri](https://avatars.discourse-cdn.com/v4/letter/s/e9a140/32.png) [@Sri](https://matillioncommunity.discourse.group/u/Sri)\ **Post date:** [October 26, 2022, 2:46pm UTC](https://matillioncommunity.discourse.group/t/trying-to-connect-to-an-oracle-data-source/1324/14 "2022-10-26T14:46:57Z")
When you meant New Instance, did you spin up a New VM?   If yes, then the IP will change. So, you've to work with Infra team to add the New IP to your Firewall setting if you have one.   Thanks, Sri ---
**Author:** ![jubith.kariyath](https://sea2.discourse-cdn.com/flex002/user_avatar/matillioncommunity.discourse.group/jubith.kariyath/32/967_2.png) [@jubith.kariyath](https://matillioncommunity.discourse.group/u/jubith.kariyath)\ **Post date:** [November 2, 2022, 6:17am UTC](https://matillioncommunity.discourse.group/t/trying-to-connect-to-an-oracle-data-source/1324/15 "2022-11-02T06:17:05Z")
We could finally resolve the issue.   There was a conflict between the packet size sent by our network firewall and that can be received by our Oracle DB. The firewall was sending more than the MTU (maximum transmission unit) and hence the oracle was rejecting the request.   Our network team made the necessary changes and is working fine now.   ---
**Author:** ![Sri](https://avatars.discourse-cdn.com/v4/letter/s/e9a140/32.png) [@Sri](https://matillioncommunity.discourse.group/u/Sri)\ **Post date:** [October 25, 2022, 2:00pm UTC](https://matillioncommunity.discourse.group/t/trying-to-connect-to-an-oracle-data-source/1324/16 "2022-10-25T14:00:17Z")
Thanks. I'll try that instead of Host name. ---
**Author:** ![jubith.kariyath](https://sea2.discourse-cdn.com/flex002/user_avatar/matillioncommunity.discourse.group/jubith.kariyath/32/967_2.png) [@jubith.kariyath](https://matillioncommunity.discourse.group/u/jubith.kariyath)\ **Post date:** [October 27, 2022, 6:30am UTC](https://matillioncommunity.discourse.group/t/trying-to-connect-to-an-oracle-data-source/1324/17 "2022-10-27T06:30:57Z")
the bash script returns a success message. but the connection error still persists.