What is the maximum number of ssh connections we can do and how can i check in linux

Question

http://www.russellyazbeck.com/aanasea

After filling out the form and downloading the PDF it opens in the browser window and all fields are populated correctly. I then right click and save as and then open the PDF in Adobe Reader. All inventory fields are gone. Even if I go to Tools > Fields > Edit Fields the inventory fields are non-existent.

However if I run 'pdftk doc.pdf dump_data_fields' on the same exact PDF I can see that the inventory fields do in fact exist with the corresponding values.

Why is the stand-alone Reader not seeing these fields?

I created this PDF in Adobe Acrobat, exported the field.fdf file, merged them using pdftk, and then output the template.pdf using pdftk.

http://www.russellyazbeck.com/aanasea/template.pdf

and here is the PHP

<?php

    require('fpdm.php');
    $today = date("F j, Y"); 

    $fields = array(
        'todaysDate'     => $today,
        'invoiceNumber' => $_POST["invoice_number"],
        'customerName'  => $_POST["customer_name"],
        'customerName2'  => $_POST["customer_name"],
        'address'        => $_POST["address"],
        'cityStateZip' => $_POST["city"] . ', ' . $_POST["state"] . ' ' . $_POST["zip"],
        'phoneNumber'   => $_POST["phone_number"],
        'email'          => $_POST["email"], 
        'rentalDates'   => $_POST["date_from"] . " - " . $_POST["date_to"],
    );

    $inventory = array (
        $_POST["inventory0"],
        $_POST["inventory1"],
        $_POST["inventory2"],
        $_POST["inventory3"],
        $_POST["inventory4"],
        $_POST["inventory5"],
        $_POST["inventory6"],
        $_POST["inventory7"],
        $_POST["inventory8"],
        $_POST["inventory9"],
        $_POST["inventory10"],
        $_POST["inventory11"],
        $_POST["inventory12"],
        $_POST["inventory13"],
        $_POST["inventory14"],
        $_POST["inventory15"],
        $_POST["inventory16"],
        $_POST["inventory17"],
        $_POST["inventory18"],
    );

    $unit = array (
        $_POST["unit0"],
        $_POST["unit1"],
        $_POST["unit2"],
        $_POST["unit3"],
        $_POST["unit4"],
        $_POST["unit5"],
        $_POST["unit6"],
        $_POST["unit7"],
        $_POST["unit8"],
        $_POST["unit9"],
        $_POST["unit10"],
        $_POST["unit11"],
        $_POST["unit12"],
        $_POST["unit13"],
        $_POST["unit14"],
        $_POST["unit15"],
        $_POST["unit16"],
        $_POST["unit17"],
        $_POST["unit18"],
    );

    $price = array (
        $_POST["price0"],
        $_POST["price1"],
        $_POST["price2"],
        $_POST["price3"],
        $_POST["price4"],
        $_POST["price5"],
        $_POST["price6"],
        $_POST["price7"],
        $_POST["price8"],
        $_POST["price9"],
        $_POST["price10"],
        $_POST["price11"],
        $_POST["price12"],
        $_POST["price13"],
        $_POST["price14"],
        $_POST["price15"],
        $_POST["price16"],
        $_POST["price17"],
        $_POST["price18"],
    );

    $subtotal = 0;

    for ($i=0, $z=count($inventory); $i<=$z; $i++) {
        $subtotal = $subtotal + ($unit[$i] * $price[$i]);
    }

    $subtotal = $subtotal;
    $deposit = $subtotal * ($_POST["deposit"] / 100);
    $tax = $subtotal * ($_POST["tax"] / 100);
    $deductions = $_POST["deductions"]; 
    $balanceDue = $subtotal + $tax - $deductions;
    $allTotal = $subtotal + $tax;
    $c = 0;

    for ($i=0, $z=count($inventory); $i<=$z; $i++) {
        if ($inventory[$i] !== NULL) {
            $fields[inventory . $c] = $inventory[$i];
            $fields[unit . $c] = $unit[$i];
            $fields[price . $c] = "$" . money_format('%i', $price[$i]);
            $fields[total . $c] = "$" . money_format('%i', ($unit[$i] * $price[$i]));
            $c++;
        }
    };
    $fields[subtotal] = "$" . money_format('%i', $subtotal);            
    $fields[deposit] = "$" . money_format('%i', $deposit);
    $fields[tax] = "$" . money_format('%i', $tax);
    $fields[deductions] = "$" . money_format('%i', $deductions);
    $fields[balanceDue] = "$" . money_format('%i', $balanceDue);
    $fields[allTotal] = "$" . money_format('%i', $allTotal);

    $pdf = new FPDM('template.pdf');
    $pdf->Load($fields, true); // second parameter: false if field values are in ISO-8859-1, true if UTF-8
    $pdf->Merge();
    $pdf->Output();

?>

Solution

I think what you're looking for is in the man sshd_config, the MaxSessions and MaxStartups fields

http://www.openbsd.org/cgi-bin/man.cgi/OpenBSD-current/man5/sshd_config.5?query=sshd_config&sec=5

File and path:

 /etc/ssh/sshd_config

Comments

[mkl]

Unfortunately your pdf link returns a 404 error. I would assume, though, that its Form is a hybrid xfa and AcroForm Form. Your code, your browser, and pdftk only see / manipulate the AcroForm part but Adobe Reader displays the xfa information.

[ryazbeck]

Fixed the pdf link. I'll check out those things you mentioned. Thanks.

[mkl]

I looked at the pdf. It does not contain a hybrid Form stricture as i assumed. Thus, could you also provide a filed-in pdf.

[ryazbeck]

You can download a filled in pdf at the first link I provided.

[Jakuje]

It really depends on what you want limit. Per user logins can be limited in /etc/security/limits.conf. Also the daemon is limited to maximum number of processes that can create and number of open files (every connection opens a file).

[mkl]

Well, one way would be to edit your original PDF in a hex editor overwriting the /Parent 146 0 R entries in the form field dictionaries of inventory0..inventory9 with spaces. You have to work carefully, though, those entries need to be overwritten, not cut away, because that would change object positions which would require you to rebuild the cross references in the PDF. I don't know whether any standard PDF tool allows that change. BTW: Adobe Acrobat Preflight additionally warns that the page content is not 100% ok. You might want to re-create the PDF from scratch without such issues.

[Jakuje]

This is actually not true. MaxSessions is related to sessions in one TCP connection and MaxStartups apply only for number of simultanous unauthenticated connections.