CODEWITHSUNDEEP
c#amazon-web-servicesaws-lambda
Ged White
Ged White

Reputation: 31

AWS Lambda Function (c#) - Works in debug mode, but errors occur once published

I am new to Amazon Web Services Lambda functions, and I decided to write a small function to ping a website. We have a VPC subnet and security group already set up, which I applied to my function when I published it.

When I run this small function in debug mode through Visual Studio it works okay, but once I publish it to AWS Lambda it fails and I get an exception:

System.Net.NetworkInformation.PingException: An exception occurred during a Ping request. ---> System.PlatformNotSupportedException: The system's ping utility could not be found.\n at System.Net.NetworkInformation.Ping.SendWithPingUtility(IPAddress address, Byte[] buffer, Int32 timeout, PingOptions options)\n at System.Net.NetworkInformation.Ping.SendPingAsyncCore(IPAddress address, Byte[] buffer, Int32 timeout, PingOptions options)\n at System.Net.NetworkInformation.Ping.GetAddressAndSendAsync(String hostNameOrAddress, Int32 timeout, Byte[] buffer, PingOptions options)\n --- End of inner exception stack trace ---\n at System.Net.NetworkInformation.Ping.GetAddressAndSendAsync(String hostNameOrAddress, Int32 timeout, Byte[] buffer, PingOptions options)\n at TestPingWebsite.Function.FunctionHandler(String input, ILambdaContext context) in C:\Users\GWhite\source\TestingWebsite\TestPingWebsite\TestPingWebsite\Function.cs:line 26

Can anybody help me understand why this error occurs please?

Upvotes: 3

Views: 721

Answers (1)

richzilla
richzilla

Reputation: 42062

AWS lambda does not support outbound ICMP (the protocol that drives ping) traffic. In addition to this, the underlying infrastructure to create the ping messages isnt supported either.

From the AWS docs (https://aws.amazon.com/lambda/faqs/):

Q: What restrictions apply to AWS Lambda function code?

Lambda attempts to impose as few restrictions as possible on normal language and operating system activities, but there are a few activities that are disabled: Inbound network connections are blocked by AWS Lambda, and for outbound connections only TCP/IP and UDP/IP sockets are supported, and ptrace (debugging) system calls are blocked. TCP port 25 traffic is also blocked as an anti-spam measure.

Upvotes: 1

Related Questions