Re: connection to backend smtp server is being reset

Roman Gelfand <[email protected]>
Newsgroups gmane.linux.keepalived.devel
Message-ID <CAJbW+rmhqWvBGqbnrk_UXAi7mj0VW+3Dhjnp-mMOZXCuQJN+tg@mail.gmail.com>
> Can you connect directly from the keepalived machine to each real server using 'telnet 192.168.0.244 25' and 'telnet 192.168.0.245 25' ?

yes

> Do you have the VIP IP address bound to the loopback address on each of the real servers (check with 'ip add show lo')?

root@pmx11:~# ip add show lo
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 16436 qdisc noqueue state UNKNOWN
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
    inet 192.168.0.249/32 brd 192.168.0.255 scope global lo:249

root@pmx12:~# ip add show lo
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 16436 qdisc noqueue state UNKNOWN
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
    inet 192.168.0.249/32 brd 192.168.0.255 scope global lo:249


> Do you have the following values set on each real server?
        echo 2 > /proc/sys/net/ipv4/conf/lo/arp_announce
        echo 1 > /proc/sys/net/ipv4/conf/lo/arp_ignore
        echo 2 > /proc/sys/net/ipv4/conf/all/arp_announce
        echo 1 > /proc/sys/net/ipv4/conf/all/arp_ignore
yes


I, also, installed the latest stable version and changed the config
since the previous email.  Nothing helped.

root@lb1:~# ipvsadm -L -n
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn
TCP  192.168.0.249:25 rr persistent 360
  -> 192.168.0.244:25             Route   1      0          0
  -> 192.168.0.245:25             Route   1      0          0

There is, also, this in the log IPVS: Can't initialize ipvs: Protocol
not available

Nov 21 19:19:14 lb1 Keepalived[2577]: Starting Keepalived v1.2.9 (11/20,2013)
Nov 21 19:19:14 lb1 Keepalived[2578]: Starting Healthcheck child
process, pid=2579
Nov 21 19:19:14 lb1 Keepalived[2578]: Starting VRRP child process, pid=2580
Nov 21 19:19:14 lb1 Keepalived_vrrp[2580]: Registering Kernel netlink reflector
Nov 21 19:19:14 lb1 Keepalived_vrrp[2580]: Registering Kernel netlink
command channel
Nov 21 19:19:14 lb1 Keepalived_vrrp[2580]: Registering gratuitous ARP
shared channel
Nov 21 19:19:14 lb1 Keepalived_vrrp[2580]: Initializing ipvs 2.6
Nov 21 19:19:14 lb1 Keepalived_healthcheckers[2579]: Initializing ipvs 2.6
Nov 21 19:19:14 lb1 kernel: [    5.538416] nf_conntrack version 0.5.0
(8023 buckets, 32092 max)
Nov 21 19:19:14 lb1 Keepalived_vrrp[2580]: IPVS: Can't initialize
ipvs: Protocol not available
Nov 21 19:19:14 lb1 Keepalived_vrrp[2580]: Opening file
'/etc/keepalived/keepalived.conf'.
Nov 21 19:19:14 lb1 Keepalived_vrrp[2580]: Configuration is using : 61430 Bytes
Nov 21 19:19:14 lb1 kernel: [    5.546153] IPVS: Registered protocols
(TCP, UDP, SCTP, AH, ESP)
Nov 21 19:19:14 lb1 kernel: [    5.546171] IPVS: Connection hash table
configured (size=4096, memory=64Kbytes)
Nov 21 19:19:14 lb1 kernel: [    5.546281] IPVS: Creating netns size=2088 id=0
Nov 21 19:19:14 lb1 kernel: [    5.546284] IPVS: ipvs loaded.
Nov 21 19:19:14 lb1 Keepalived_healthcheckers[2579]: Registering
Kernel netlink reflector
Nov 21 19:19:14 lb1 Keepalived_healthcheckers[2579]: Registering
Kernel netlink command channel
Nov 21 19:19:14 lb1 Keepalived_healthcheckers[2579]: Opening file
'/etc/keepalived/keepalived.conf'.
Nov 21 19:19:14 lb1 Keepalived_healthcheckers[2579]: Configuration is
using : 12533 Bytes
Nov 21 19:19:14 lb1 Keepalived_vrrp[2580]: Using LinkWatch kernel
netlink reflector...
Nov 21 19:19:14 lb1 Keepalived_healthcheckers[2579]: Using LinkWatch
kernel netlink reflector...
Nov 21 19:19:14 lb1 Keepalived_healthcheckers[2579]: Activating
healthchecker for service [192.168.0.245]:25
Nov 21 19:19:14 lb1 Keepalived_healthcheckers[2579]: Activating
healthchecker for service [192.168.0.244]:25
Nov 21 19:19:14 lb1 kernel: [    5.574016] IPVS: [rr] scheduler registered.
Nov 21 19:19:14 lb1 mpt-statusd: detected non-optimal RAID status
Nov 21 19:19:15 lb1 Keepalived_vrrp[2580]: VRRP_Instance(VI_1)
Transition to MASTER STATE
Nov 21 19:19:16 lb1 Keepalived_vrrp[2580]: VRRP_Instance(VI_1)
Entering MASTER STATE




root@lb1:~# ifconfig
eth0      Link encap:Ethernet  HWaddr 00:0c:29:91:4f:8a
          inet addr:192.168.0.250  Bcast:192.168.0.255  Mask:255.255.255.0
          inet6 addr: fe80::20c:29ff:fe91:4f8a/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:2498 errors:0 dropped:0 overruns:0 frame:0
          TX packets:921 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:262390 (256.2 KiB)  TX bytes:83660 (81.6 KiB)

eth0:0    Link encap:Ethernet  HWaddr 00:0c:29:91:4f:8a
          inet addr:192.168.0.249  Bcast:192.168.0.255  Mask:255.255.255.0
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1

lo        Link encap:Local Loopback
          inet addr:127.0.0.1  Mask:255.0.0.0
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU:16436  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B)


My new config is...

global_defs  {
lvs_id  LVS_1
}
vrrp_instance  VI_1  {
       interface  eth0
       state  MASTER
       virtual_router_id  51
       priority  101                     # 101 on master, 100 on backup
       advert_int  1
       smtp_alert
authentication  {
auth_type  PASS
auth_pass  pass

}

       virtual_ipaddress  {
           192.168.0.249/24
}

 virtual_server  192.168.0.249  25  {
   delay_loop  60
   lb_algo  rr
   lb_kind  DR
   protocol  TCP
   persistence_timeout  360

   real_server 192.168.0.245 25 {
   weight 1
       TCP_CHECK {
               connect_timeout 3
       connect_port 25
       nb_get_retry 3
       delay_before_retry 3
       }
   }
   real_server 192.168.0.244 25 {
       weight 1
       TCP_CHECK {
               connect_timeout 3
       connect_port 25
       nb_get_retry 3
       delay_before_retry 3
       }
   }
}

On Thu, Nov 21, 2013 at 2:49 PM, Todd Fleisher <[email protected]> wrote:
> Can you connect directly from the keepalived machine to each real server using 'telnet 192.168.0.244 25' and 'telnet 192.168.0.245 25' ?
>
> Do you have the VIP IP address bound to the loopback address on each of the real servers (check with 'ip add show lo')?
>
> Do you have the following values set on each real server?
>         echo 2 > /proc/sys/net/ipv4/conf/lo/arp_announce
>         echo 1 > /proc/sys/net/ipv4/conf/lo/arp_ignore
>         echo 2 > /proc/sys/net/ipv4/conf/all/arp_announce
>         echo 1 > /proc/sys/net/ipv4/conf/all/arp_ignore
>
> -T
>
> On Nov 20, 2013, at 11:17 AM, Roman Gelfand wrote:
>
>> I am trying to connect, from a workstation, to backend smtp server via
>> keepalived lb using command telnet 192.168.0.249 25.  The connection
>> is being reset.
>>
>> trace take on machine running keepalived
>> -------------------------------------------------------------
>>
>> 90 18:28:37.116176 192.168.0.209 192.168.0.249 TCP 66 54121 > smtp
>> [SYN] Seq=0 Win=8192 Len=0 MSS=1460 WS=4 SACK_PERM=1
>> 112 18:28:43.116442 192.168.0.209 192.168.0.249 TCP 62 [TCP
>> Retransmission] 54121 > smtp [SYN] Seq=0 Win=8192 Len=0 MSS=1460
>> SACK_PERM=1
>>
>> trace taken from machine running postfix smtp server
>> ------------------------------------------------------------------------------
>>
>> 135 18:29:32.180241 192.168.0.250 192.168.0.244 TCP 74 59566 > smtp
>> [SYN] Seq=0 Win=14600 Len=0 MSS=1460 SACK_PERM=1 TSval=4616943 TSecr=0
>> WS=16
>> 136 18:29:32.180292 192.168.0.244 192.168.0.250 TCP 74 smtp > 59566
>> [SYN, ACK] Seq=0 Ack=1 Win=14480 Len=0 MSS=1460 SACK_PERM=1
>> TSval=2535443 TSecr=4616943 WS=32
>> 137 18:29:32.180435 192.168.0.250 192.168.0.244 TCP 66 59566 > smtp
>> [ACK] Seq=1 Ack=1 Win=14608 Len=0 TSval=4616943 TSecr=2535443
>> 138 18:29:32.180480 192.168.0.250 192.168.0.244 TCP 66 59566 > smtp
>> [RST, ACK] Seq=1 Ack=1 Win=14608 Len=0 TSval=4616943 TSecr=2535443
>>
>>
>> Not sure why it is not working.
>>
>>
>> my topology is as follows.
>>
>>           lb1 (keepalived server)  host mx...   eth0  vip .249, eth1 ip .250
>>                     ||
>>                     ||
>>                     ||
>>          ========================
>>          ||                                             ||
>>          ||                                             ||
>>          ||                                             ||
>> host mx1...  ip .244 (postfix smtp)     host mx2... ip .245 (postfix smtp)
>>
>> On each m1... and mx2... mail servers I added
>>
>> My config is...
>>
>> global_defs  {
>> lvs_id  LVS_1
>> }
>> vrrp_instance  VI_1  {
>>       interface  eth1
>>       state  MASTER
>>       virtual_router_id  51
>>       priority  101                     # 101 on master, 100 on backup
>>       advert_int  1
>>       smtp_alert
>> authentication  {
>> auth_type  PASS
>> auth_pass  pass
>>
>> }
>>
>>       virtual_ipaddress  {
>>           192.168.0.249/24  brd  192.168.0.255  dev  eth0
>> }
>>
>> virtual_server  192.168.0.249  25  {
>>   delay_loop  60
>>   lb_algo  rr
>>   lb_kind  DR
>>   protocol  TCP
>>   persistence_timeout  360
>>
>>   real_server 192.168.0.245 25 {
>>   weight 1
>>       TCP_CHECK {
>>               connect_timeout 3
>>       connect_port 25
>>       nb_get_retry 3
>>       delay_before_retry 3
>>       }
>>   }
>>   real_server 192.168.0.244 25 {
>>       weight 1
>>       TCP_CHECK {
>>               connect_timeout 3
>>       connect_port 25
>>       nb_get_retry 3
>>       delay_before_retry 3
>>       }
>>   }
>> }
>>
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>
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