Want to protect your cyber security and still get fast solutions? Ask a secure question today.Go Premium



Posted on 1998-11-23
Medium Priority
Last Modified: 2010-03-18
I have Redhat Linux running on a server and 6 win95 nodes connected to it. File, Print etc. network services are working fine.

I have an internet account with my ISp and my email address is "xxxx@yyyy.zzz.in" All my email is being received in this address and reply address set in my mail client is alos the same. Currently I am using a win95 pc to do the mail
handling. User name: "xxxx@yyyy.zzz.in" password "qqqq"
for logging in.

Now I want the linux server should send and collect mail automatically every hour. All the mail collected should be sent to two users say "aaaaa" and "bbbbb" who have user accounts on the server. Moreover all users should be able to send mail to the outside world over internet with their reply address set as above. Using the Outlook Express mail clinet in their boxes.

The DNS of my ISP is 111.222.333.444 and alternate DNS is

IP setting of my server is and IP to nodes are given dynamically by the DHCP range -

PPP connection using PPPD has being sucessfully setup along with login options. However even from the Server sendmail cannot send mail to outside world or fetchmail cannot retrieve mail from my ISP. It gives ups showing a message that it cannot resolve the server name in the email address given.

Request for the following solution.
1. Sendmail settings with the above information
2. Fetchmail Setting with the above information
3. DNS setting with the above information
4. Sample configuration files for the above

In the linux server Sendmail, POP3 has been installed with default setting. DHCP and DNS has also been setup by default.

The linux server is known as linux.kscpl.com in the network.
Question by:kathotia
  • 4
  • 2
  • 2
  • +1

Expert Comment

ID: 1587677

Did you put the ip addresses of your ISP's nameservers in


Author Comment

ID: 1587678
YES I have put my ISP's DNS Ip in resolv.conf but still DNS does not seem to work.

Expert Comment

ID: 1587679
DNS is working at all? In your linux box, is it possible to run nslookup and do name queries?
Concerto Cloud for Software Providers & ISVs

Can Concerto Cloud Services help you focus on evolving your application offerings, while delivering the best cloud experience to your customers? From DevOps to revenue models and customer support, the answer is yes!

Learn how Concerto can help you.


Author Comment

ID: 1587680
I have through trial and error detected that the DNS is not working properly. Other componenets have been set up correctly. Sendmail gives a message " Name Server timed out" and fetchmail gives message "unable to find name .....". I have read DNS howto thereafter and tried nslookup as stated therin after initiating a pppp link by running pppd with necessary parameters. ifconfig shows a valid and working ppp link working at ppp0. I am able to ping the remote ip address shown by the ipconfig. but i am not able to pind the DNS IP of my ISP as stated above. nslookup also fails to show any results when asked for anu other domain name outside my personal network.

I have checked all the files as per DNS howto but fail to find any error. If you want ot look up the said files kindly give your email address I will mail the files to you for study.

thanks for devting time to my problem.

Expert Comment

ID: 1587681
If you cannot ping the DNS server using the IP address (not the name) then you have a routing problem.

Run "route -n" to see if you have a default gateway (address to your ISP network. You also can use traceroute to see where you are stopping.

Check to see if you are starting pppd with the option "defaultroute".

You will never be able to use your DNS before you be able to ping your DNS.


Author Comment

ID: 1587682
I checked up with route -n and found that default route was not being replaced by pppd. I created a default route manually by giving the command
 /sbin/route del default
 /sbin/route add default gw $4 dev ppp0

After this route -n showed the necessary gateway and every thing worked fine. However it seems that pppd is not calling and running ip-up which in turn calls ip-up.local wherein I have put up the above two commands. So I have to manually give the commands every time i run pppd. moreover since ip-up is not executed i am not able to know whether ppd has been successful or not in getting through.

Kindly advise
Thanks again for showing the light


Expert Comment

ID: 1587683
 "IP setting of my server is and IP to nodes are given dynamically by the DHCP range -"
is a typo, otherwise your clients are on different networks to your server. Which will require further routing table entries.
Things to do to solve problem are:
Setup named (DNS) to be a caching nameserver, point to in /etc/resolv.conf. Use diald to initiate dial on demand pppd, it can use all the existing pppd options in its config files.If you insist on manual dial, as fmismetti said, use the defaultroute config switch to make this interface the default route.
If your ISP can support SMTP delivery to you, you can then use sendmail to receive all e-mail for yyyy.zzzz.in domain, ie anybody@yyyy.zzzz.in. If they do, they may do this by forwarding mail to you when you dial in, or you may need to use the SMTP command ETRN yyyy.zzzz.in to inititate the transfer. For this to work you need to get your ISP to make your host name the primary MX for the domain. This will require a static IP address from them. To get your mail to retrieve every hour you could set up a shell script to send ETRN yyyy.zzzz.in to SMTP port (25) on your ISP mail server every hour by scheduling its execution with cron. Hopefully you can find out the config, otherwise I'll need to spend ages finding appropriate config files for you. Let me know !

Author Comment

ID: 1587684
Py problem presently after allthe experimenting and corrections is to setup the default route automatically ecah time I dial. the dettinf "defaultroute" in options file fails to replace the existing defaultroute pointing to eth0. I have to manually set the default route ot ppp0 which i want ot automate. Rest of my problems has been solved. Kindly go throuhg my last comment for details.

Accepted Solution

irp earned 300 total points
ID: 1587685
Try not putting a default route in your startup to eth0, just add the route to the network and any networks reached via the ethernet. Then add defaultroute to your ppp options file, or pass it as a command line parameter. Make sure you are not using -defaultroute as this means don't do it. Just pppd /dev/ttyS1 defaultroute etc. etc, or options file

Featured Post

Industry Leaders: We Want Your Opinion!

We value your feedback.

Take our survey and automatically be enter to win anyone of the following:
Yeti Cooler, Amazon eGift Card, and Movie eGift Card!

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

I have seen several blogs and forum entries elsewhere state that because NTFS volumes do not support linux ownership or permissions, they cannot be used for anonymous ftp upload through the vsftpd program.   IT can be done and here's how to get i…
Note: for this to work properly you need to use a Cross-Over network cable. 1. Connect both servers S1 and S2 on the second network slots respectively. Note that you can use the 1st slots but usually these would be occupied by the Service Provide…
If you're a developer or IT admin, you’re probably tasked with managing multiple websites, servers, applications, and levels of security on a daily basis. While this can be extremely time consuming, it can also be frustrating when systems aren't wor…
Despite its rising prevalence in the business world, "the cloud" is still misunderstood. Some companies still believe common misconceptions about lack of security in cloud solutions and many misuses of cloud storage options still occur every day. …
Suggested Courses

578 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question