Kermit Software - FTP Instructions and Tips

`Kermit Software - FTP Instructions and Tips`

READ THIS FIRST:

August 2011: Due to the proliferation of firewalls, network address translators, and the like, FTP — a fundamental Internet standard since 1971 — has become increasingly problematic. For this reason, access to the entire Kermit software archive is now available through your Web browser via HTTP protocol (the protocol used by Web browsers), which for all practical purposes, is never blocked. Now, for the first time, you can download any Kermit program with its source code by clicking on a link to a Zip or Tar.gz file. CLICK HERE to visit the archive. The rest of this page is about FTP, which (as of this writing) is still available for those who are not blocked from using it.

CONTENTS

INSTRUCTIONS
IF YOU HAVE TROUBLE

INSTRUCTIONS

The primary ftp site for Kermit software is:

ftp://kermit.columbia.edu/kermit/

Or in non-Web notation (more about this below):

ftp.kermit.columbia.edu
kermit.columbia.edu
ftp.columbia.edu

There is no ftp-mail server, and we do not send Kermit software by email -- in most cases it is too big to survive the trip.

These days, the easiest way to access the Kermit ftp site is with a Web browser. Our Web address is:

http://www.columbia.edu/kermit/

A page giving quick access to the current releases of the most popular Kermit programs is here:

http://www.columbia.edu/kermit/current.html

The web pages guide you easily to the files you need, and give you all the other information you might want -- frequently asked questions, licensing information, etc.

But of course there are drawbacks. Many Web-browser FTP clients give you no control over the mode (text or binary) in which the file is downloaded, nor what becomes of the file after it is downloaded. Furthermore, some Web browsers do not allow FTP transfer of file groups -- only one file at a time may be transferred.

Hint: In most browsers, you might have to right-click on a filename and choose "Save" to make it download, rather than appear as garbage on your screen, or have it fed to a random application.

Windows-based graphical FTP clients are especially annoying, as they like to choose "helper applications" for the file you are trying to download, based on its name, on the often erroneous assumption that it's a Windows file. In the Kermit ftp area, ".doc" files are plain text, not Word For Windows; ".hlp" files are plain text, not Windows Help, and so on. Binaries such as "cku197.sunos41c-4.1.3-sparc" or "k11nrs.tsk" are simply to be ftp'd in binary mode and saved, not associated with any Windows application.

Some of the graphical FTP clients can surprise you; they download the file, but then you can't find it afterwards, either because it put it in a directory you weren't expecting, or it changed the name of the file (case of letters, adding numbers to the end, etc). Or they transferred in binary mode when you needed text mode, or vice versa.

If your Web browser or graphical FTP client can't cope with downloads, then use FTP the Old Fashioned Way. Open a Command window on your Windows PC, or a shell window on your UNIX workstation, etc. Then, at the DOS / shell prompt:

(DOS, Windows, or OS/2 only): Type the disk letter of the disk you want to download to, followed by a colon (:), for example, "d:", and then press the Enter key.
Change to the directory that you want to download to, e.g.:
```
  cd tmp
```
Type:
```
  ftp kermit.columbia.edu
```
and then press the Enter or Return key.
It will prompt you:
```
  User (kermit.columbia.edu):
```
In response, type the word "anonymous" (lowercase, spelled out in full) and then press the Enter or Return key.
Now it will prompt you for a password. In response, type your email address and then press the Enter or Return key. You should receive a greeting and a brief overview of the available directories, "kermit" among them.
Now type "cd kermit" (lowercase) and press the Enter or Return key. You should receive another orientation message. Read this message and follow the directions.

Now you can cd to the desired subdirectories and look around. Each time you cd, you should receive an orientation message for the new directory. Use the FTP "dir" command to list the files in the current directory, "pwd" to find out which directory you are in.

To download text files, first give the FTP "ascii" command, then use the FTP "get" command to download a single file, or "mget" to download multiple files. Please note: If you download text files in binary mode, their record formats might be wrong, but they should still be readable. If the GET or MGET command fails, see the troubleshooting section below.

To download binary files, first give the FTP "binary" command, then use the FTP "get" command to download a single file, or "mget" to download multiple files. Please note: If you download binary files in "ascii" (or text) mode, they will be completely corrupted and you won't be able to use them.

When you are finished, give the ftp "bye" command.

If you download an executable file to UNIX, you have to "chmod +x" the file before you can run it ("man chmod" for details).

CONVERTING AN FTP URL INTO AN HTTP URL This procedure applies to only the Columbia FTP site.

You can transform any Kermit Project FTP link into an HTTP one to bypass the firewall. For example, this link:

ftp://kermit.columbia.edu/kermit/archives/cku301.tar.gz

becomes (by changing “ftp:” to “http:” and “/kermit/” to “/ftp/”):

http://kermit.columbia.edu/ftp/archives/cku301.tar.gz

IF YOU HAVE TROUBLE

The Kermit FTP site should be available 24 hours a day, 7 days a week, and serves thousands of files every day to sites all over the world. There are presently no limitations on the number of simultaneous users, the number or size of files you can request, etc. If you have trouble getting into our FTP server, the trouble is almost certainly on your end.

Our FTP server has enough power to keep up with the demand. If you think it is slow, the slowness most likely comes from the Internet connection itself, not from our FTP server. However, in the 24-48 hours after a major Kermit software announcement, the demand can be quite heavy, and this can slow down not only the server, but also key gateways or routers, contention-based network segments, etc. A fact of life. Nevertheless, any time we get complaints that the server is down or not responding, they almost never turn out to be true; inspection of the server usually shows lots of active users at any given time, day or night.

If you have trouble:

If you are not able to download a particular file with FTP, try HTTP. Visit THIS PAGE and simply click on the file's name.
First make sure that your organization does not have some kind of firewall that prevents FTP connections. If it does, then contact your local network administrators for advice. (Although FTP uses a well-known port number for its control connection, it uses a random port number for its data connection, and so might not work through firewalls.) If your FTP client has a PASSIVE (or PASV) command, give this command before attempting to transfer any files.
If your connection times out, then the network is congested or busy, or your local network is misconfigured, or there is a malfunction or outage on the Internet, or (rarely) the Kermit ftp server is down. In all such cases, try again later.
"kermit.columbia.edu" might be (and usually is) an alias for some other hostname at Columbia, such as www-akamai-vif.cc.columbia.edu, or www-csm.cc.columbia.edu, or redleaf.cc.columbia.edu. These hostnames resolve to the same IP address, so this should not cause a problem if our site has a rule like the one just below. Don't use the "real" name, as it can change from time to time, whereas the name kermit.columbia.edu is constant. In case the aliasing causes trouble with your ftp client or network security setup, some reconfiguring might be needed on your end.
If your connection is refused, it is most likely because of a misconfiguration in the Domain Name Service (DNS) for the IP address that is being used to connect to the Kermit FTP site. (If you are connecting through a firewall/proxy the IP address that matters is the one on the far end of the firewall/proxy; not the one on your local machine.) Columbia University policy requires that all TCP services (including the Kermit FTP server) query DNS regarding the IP address of each incoming connection to get its associated hostname, and then look up the hostname to make sure it resolves to the same IP address. This is a standard security measure that is being instituted on an ever widening basis throughout the world to prevent IP address spoofing. Your connection is closed immediately if:
- The IP address assigned to the computer you are using cannot be identified by name (no DNS entry, or the DNS entry is not exported, for example because it is behind a firewall); or:
- The name associated with the IP address is assigned to a different IP address; or:
- The name associated with the IP address is not a valid DNS entry.
If you want to use Columbia University TCP services, you must have a proper DNS entry for your computer, and you must export it so that the Columbia University FTP server can look it up. If this is not the case, ask your ISP or network administrators to rectify the situation (or use HTTP instead of FTP to retrieve Kermit files).
- But I can make FTP connections to other sites! The fact that you can get to other FTP sites is only because they don't have security policies in place that are sufficient to protect themselves against hostile attacks. Once they are attacked, they will institute such policies and then you won't be able to get to them either until you fix your DNS to properly respond to queries for the host you are coming from.
If your connection is accepted but immediately closed, check to see if your computer is running "identd". If so, be sure it is not configured to reject authentication requests (this applies if Columbia is running an FTP server secured by SSL or Kerberos, which might not always be the case).
If you can log in successfully but GET or MGET commands fail, switch ACTIVE / PASSIVE modes; i.e. if your FTP client was in ACTIVE mode, give a PASSIVE command, or vice versa.
If GET or MGET commands take forever, try a different FTP client (especially if you are using Internet Explorer), or use an HTTP link to the desired file if one is available.
If you make a connection successfully, but have trouble after you log in, maybe your ftp client is confused by the greeting and orientation messages. In that case, give the "bye" command and then make a new connection and enter a password that begins with a hyphen (-). This disables the messages.
If you can't find what you are looking for, get and read the aaareadme.txt, README.TXT, READ.ME, readme.txt, read.me, or .readme file and read it. Each directory should have one of these. But in most cases it is much easier to find what you need using the Web interface. Check these pages:
- Current Versions
- Script Library
If you are trying to download the Kermit 95 Trial Version without success, you can also get it direct from our Internet distributor, e-academy.com.
If you are trying to download a new copy of a file (e.g. because we told you we replaced it), but you keep getting the old copy, it's because your ftp client goes through some kind of cache (e.g. a proxy Web server) and due to a bug, time skew, or other problem in your network, the cache is not refreshed when the real file changes. Problems like this can be fixed only by your network manager, ISP, or webmaster.

Kermit Software - FTP Tips / Columbia University / kermit@columbia.edu / 29 Aug 2011