Aurelin's questions

I currently am dealing with a client whose e-mail is hosted on Google. We are just in the process of taking over their domain, but their current hosting company suggests a different set up than I do and I was wondering if you could tell me some technical pros and contras of one or the other set up. Say their nameserver is ns.excompany.org And our nameserver is ns.incompany.org. Our server's IP is [IP]

The set up they suggest is the following: DNS for domain points to ns.excompany.org They have an A-record pointing to [IP] for the website They have an MX-record pointing to Google for mail

The set up I suggest is DNS for domain points to ns.incompany.org We have an MX-record pointing to Google for mail

The things that came to my mind were 1. If we ever, for whatever reasons, have our server's IP address changed, they will have to change it as well. 2. The client has to keep the old hosting company and keep paying them to maintain that set up, hence pays three services when they'd only need to pay for two services.

Are there any actual technical aspects/differences you could name?

I am currently dealing with an issue where e-mails won't get delivered because exim has too many connections.

I googled around a bit and found out that maybe I should check how many instances are running, and last time I ran into this issue, I had about 140 instances running. After a restart of the service, it was down to around 10 instances for a while, but is now at over 200.

When I restarted exim, I also changed the config to allow up to 200 connections (was 100 before).

I do not know exim overly well (aka I am totally new), so what I wonder now are the following things : 1.) How many instances of exim are healthy? We have a lot of domains on the server but handle most of the emails on external services. I imagine 200 running instances are a bit too much, but maybe I am wrong?

2.) What is, on average, a good value for smtp_accept_max?

3.) If 200 instances are too many, what can I do to find out what causes it to create this amount of processes? I am not really seeing anything in the logs, but maybe I just don't know what I should look for? And also, how can I fix this if it is an issue?

I read something about changing :blackhole in all files in /etc/valiases to :fail, but when I look at a file of one of the domains that use the server as an MX, the file looks like this :

[email protected]: [email protected]
*: accountuser

Might that config file itself be the issue?

We have a couple of virtual interfaces configured on eth0 on a CentOS, and every now and then, they went down seemingly out of the blue. Now after going through the log files, I found out that apparently ntpd deletes all eth0 interfaces, and that dhclient automatically brings eth0 back up. The virtual interfaces, however, stay down which causes several of our websites to be inaccessible.

Can someone explain to me why ntpd deletes interfaces? Can / should that be turned off, or can / should I configure dhclient to bring the virtual interfaces back up automatically, too?

EDIT// The log files that I should've posted :

Nov 12 13:10:28 raptor dhclient[20048]: DHCPREQUEST on eth0 to 255.255.255.255 port 67 (xid=0x6a825e97)
Nov 12 13:10:42 raptor dhclient[20048]: DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 8 (xid=0x24554092)
Nov 12 13:10:42 raptor dhclient[20048]: DHCPOFFER from 96.126.108.78
Nov 12 13:10:42 raptor dhclient[20048]: DHCPREQUEST on eth0 to 255.255.255.255 port 67 (xid=0x24554092)
Nov 12 13:10:42 raptor dhclient[20048]: DHCPACK from 96.126.108.78 (xid=0x24554092)
Nov 12 13:10:42 raptor ntpd[2109]: Deleting interface #31 eth0, 50.116.50.97#123, interface stats: received=3255, sent=3256, dropped=0, active_time=1559394 secs
Nov 12 13:10:42 raptor ntpd[2109]: Deleting interface #32 eth0:0, 50.116.53.56#123, interface stats: received=3, sent=0, dropped=0, active_time=1559391 secs
Nov 12 13:10:42 raptor ntpd[2109]: Deleting interface #33 eth0:1, 66.175.211.192#123, interface stats: received=2, sent=0, dropped=0, active_time=1559389 secs
Nov 12 13:10:42 raptor ntpd[2109]: Deleting interface #34 eth0:2, 50.116.53.95#123, interface stats: received=3, sent=0, dropped=0, active_time=1559387 secs
Nov 12 13:10:42 raptor ntpd[2109]: Deleting interface #35 eth0:3, 97.107.132.32#123, interface stats: received=2, sent=0, dropped=0, active_time=1559385 secs
Nov 12 13:10:42 raptor ntpd[2109]: Deleting interface #36 eth0:4, 50.116.56.201#123, interface stats: received=2, sent=0, dropped=0, active_time=1559383 secs
Nov 12 13:10:42 raptor ntpd[2109]: Deleting interface #37 eth0:5, 66.175.212.121#123, interface stats: received=2, sent=0, dropped=0, active_time=1559381 secs
Nov 12 13:10:42 raptor ntpd[2109]: Deleting interface #38 eth0:6, 66.175.215.137#123, interface stats: received=2, sent=0, dropped=0, active_time=1559379 secs
Nov 12 13:10:44 raptor NET[1573]: /sbin/dhclient-script : updated /etc/resolv.conf
Nov 12 13:10:44 raptor dhclient[20048]: bound to 50.116.50.97 -- renewal in 32692 seconds.
Nov 12 13:10:45 raptor ntpd[2109]: Listening on interface #39 eth0, 50.116.50.97#123 Enabled

The eth0 config :

DEVICE="eth0"
ONBOOT="yes"
BOOTPROTO="dhcp"
IPV6INIT="no"
IPADDR=50.116.50.97
NETMASK=255.255.255.0
GATEWAY=50.116.50.1

And the virtual interfaces (I posted the first one only, they look the same for the most part) :

# Configuration for eth0:0
DEVICE=eth0:0
BOOTPROTO=none

# This line ensures that the interface will be brought up during boot.
ONBOOT=yes

# eth0:0
IPADDR=50.116.53.56
NETMASK=255.255.255.0

Is it possible to send an e-mail to a server when the MX for the domain is not on this server? I have the following set up:

• Server A with domain domain.com configured
• GMail as the Mail Exchanger

I want to set up an e-mail address to which I can send e-mails whose content will then be stored in a database. As far as I know, for that I would need to set up a postfix filter that runs a script when receiving an e-mail from said address. But for that, the server first needs to get the e-mail, which it currently doesn't.

Is there any way to forward the e-mail from the external MX to the actual server, or to completely bypass the external MX for a list of addresses?

I'm setting up an SSO for Active Directory users through a website that runs on an Apache (Apache2 on SLES 11.1), and when testing with Firefox it all works fine. But when I try to open the website in Internet Explorer 8 (Windows 7), all I get is

"Bad Request

Your browser sent a request that this server could not understand.

Size of a request header field exceeds server limit.

Authorization: Negotiate [ultra long string]"

My vhost.cfg looks like this:

<VirtualHost hostname:443>
  LimitRequestFieldSize 32760
  LimitRequestLine 32760
  LogLevel debug

  <Directory "/data/pwtool/sec-data/adbauth">
    AuthName "Please login with your AD-credentials (Windows Account)"
    AuthType Kerberos
    KrbMethodNegotiate on
    KrbAuthRealms REALM.TLD
    KrbServiceName HTTP/hostname
    Krb5Keytab /data/pwtool/conf/http_hostname.krb5.keytab
    KrbMethodK5Passwd on
    KrbLocalUserMapping on
    Order allow,deny
    Allow from all
  </Directory>

  <Directory "/data/pwtool/sec-data/adbauth">
    Require valid-user
  </Directory>

    SSLEngine on
    SSLCipherSuite ALL:!ADH:!EXPORT56:RC4+RSA:+HIGH:+MEDIUM:+LOW:+SSLv2:+EXP:+eNULL
    SSLCertificateFile /etc/apache2/ssl.crt/hostname-server.crt
    SSLCertificateKeyFile /etc/apache2/ssl.key/hostname-server.key
</VirtualHost>

I also made sure that the cookies are deleted and tried several smaller values for LimitRequestFieldSize and LimitRequestLine.

Another thing that seems weird to me is that even with LogLevel debug I won't get any logs about this. The log's last line is

ssl_engine_kernel.c(1879): OpenSSL: Write: SSL negotiation finished successfully

Does anyone have an idea about that?