When hard coding (tid,name) in the $content variable, I will able to pass the request successfully using LWP::UserAgent perl module whereas it doesn't working fine while invoking the POST method by passing the content with a string value (tid,name) in the hash array is throwing the 500 Internal Server Error. 

#! /usr/local/bin/perl
    
    use LWP::UserAgent;
    use JSON;
    
    #Variable declaration

    my $tk = 123456;
    my $tid = 1234;
    my $name = "Mark";
    
    my $url = "https://xxx/vs/v2/api/instance";
    
    #HTTP Content
    my $content =qq{
    {
    "application.name": "NBM",
    "application.version": "1.1",
    "envvars": 
    [
        {
            "id": "KEY1/m_1.1",
            "value": "
            {
                "a_a_i":
                {
                    "c_id_value":"APP",
                    "selection_type":"user",
                    "c_id_doc_v    ":"1.0",
                    "c":"sm",
                    "c_id":"sm","c_id":13
                },
                "c_a_i":
                [
                    {
                        "c_id_vue":"APP",
                        "customer_identifier":"account_id",
                        "customer_type":"unknown",
                        "licensing_model":"unknown",
                        "entitlement":
                        [
                            {
                                "entitlement_id":"id",
                                "quantity":290
                            }
                        ]
                    },
                    {
                        "customer_identifier_value":"APP",
                        "customer_identifier":"account_id",
                        "customer_type":"unknown",
                        "licensing_model":"unknown",
                        "entitlement":
                        [
                            {
                                "entitlement_id":"id",
                                "quantity":290
                            }
                        ]
                    },
                    {
                        "customer_identifier_value":"P",
                        "customer_identifier":"account_id",
                        "customer_type":"unknown",
                        "licensing_model":"unknown",
                        "entitlement":
                        [
                            {
                                "entitlement_id":"id",
                                "quantity":259
                            }
                        ]
                    }
                ]
            }
        },
        {
            "id": "KEY2/m_1.1",
            "value": ""
        },
        {
            "id": "KEY3/m_1.1",
            "value": "0"
        }
    ],
    "network": 
    [
        {
            "id": "hname/m_1.1",
            "value": "xxx.y.z.com"
        },
        {
            "id": "I/m_1.1",
            "value": "$name"
        },
        {
            "id": "ipaddress/m_1.1",
            "value": "10.20.33.xx"
        },
        {
            "id": "t/m_1.1",
            "value": "$tid"
        },
        {
            "id": "domainname/m_1.1",
            "value": "y.z.com"
        },
        {
            "id": "nameservers/m_1.1",
            "value": "17x.34.5.6"
        },
        {
            "id": "sd/m_1.1",
            "value": "y.z.com"
        },
        {
            "id": "etc/m_1.1",
            "value": ""
        }
    ],
    "volume": 
    [
        {
            "id": "ctb/m_1.1",
            "value": "25GB"
        }
    ]
    }
    };

    my $ua =LWP::UserAgent->new(
    ssl_opts => { verify_hostname => 0 });

    #POST Method with headers

    my $req = HTTP::Request->new('POST' => $url);
    $req->header ('Content-Type'=>'application/json');
    $req->header('X-Auth-Token'=>$tk);
    $req->header('Accept'=>'*/*');
    $req->header('Accept-Encoding'=>'gzip, deflate, br');
    $req->header('Connection'=>'keep-alive');
    $req->content($content);
    
    my $res = $ua->request($req);
    print $res->as_string;
    #Checking Response
    if($res->is_success)
    {
    print $res->content, "\n";
    }
    else
    {
           print $res->status_line, "\n";
    }

[download]

The output: 

    ERROR::
    HTTP/1.1 500 Internal Server Error
    Connection: close
    Date: Sun, 12 Apr 2020 07:13:47 GMT
    Server: nginx/1.12.2
    Content-Length: 78
    Content-Type: text/plain; charset=utf-8a
    Client-Date: Sun, 12 Apr 2020 07:13:47 GMT
    Client-Peer: 10.32.45.x:443
    Client-Response-Num: 1
    Client-SSL-Cert-Issuer: /C=US/ST=xxxx/O=xxx/OU=rrr/CN=x.y.z.com-in
+term2000000000000
    Client-SSL-Cert-Subject: /C=US/ST=Cxxxxxx/L=cdlf view/O=********/O
+U=XXXXXXX/CN=cons
    Client-SSL-Cipher: ZBAJSD-SBSHHS-HSJDD-****
    Client-SSL-Socket-Class: IO::Socket::SSL
    Client-SSL-Warning: Peer certificate not verified
    X-Content-Type-Options: noDFDFD
    
    {"errorCode”:”XX-XX-XXX”,”errorMessage":"Internal server error occ
+urred"}

[download]

2020-04-13 Athanasius added readmore tags to main code and code tags to error output.

In reply to Getting 500 Internal Error while calling POST method by passing content in PERL script by sathis4mailing

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