I am having a problem with what appears (to me) to be 'stale' TCP
connections for syncrepl between the master and a pair of slaves. After
restarting all, I see changes on the master replicated to both slaves.
BUT, if I wait about 30 minutes or more, then make a change, the
replication fails (most of the time). netstat on the LDAP port show the
connections still established, but queued packets at the master server.
After about 15 minutes, the master server drops the connection. An
overnight tcpdump on the master showed LDAP occasionally sending a
keep-alive, with 2hrs between the keep-alive messages (these keep-alives
are inconsistent, though, some nights I see none).
I am running Red Hat EL5 and Openldap 2.3.43 on all servers with no TLS
or SASL (in our integration/test facility).
I don't see anything in the documentation pertaining to keep-alives,
other than ITS#4708 for 2.3.38.
Here's the syncrepl for one slave:
syncrepl rid=004
type=refreshAndPersist
provider=ldap://172.24.1.191
retry="30 10 300 3"
searchbase="o=partner_x,dc=ourcompany-int,dc=net"
filter="(objectClass=*)"
scope=sub
schemachecking=off
bindmethod=simple
binddn="cn=syncRepl,o=partner_x,dc=ourcompany-int,dc=net
"
credentials="secret"
updateref ldap://172.24.1.191
The other slave's slapd.conf is indentical except rid=002.
On the master I have:
overlay syncprov
syncprov-checkpoint 100 30
syncprov-sessionlog 100
Note: The 2 slaves are running on blades in an IBM chassis, and the
master is on a 1U Linux server, just 'one-hop' away. Prior to this,
when I had a master/slave pair running on the blades, syncRepl was
working fine for several months. It was not until I moved the master to
the another server did the failures start.
Thanks in advance for any help or info.
John Kane
This message is confidential to Prodea Systems, Inc unless otherwise indicated
or apparent from its nature. This message is directed to the intended recipient
only, who may be readily determined by the sender of this message and its
contents. If the reader of this message is not the intended recipient, or an
employee or agent responsible for delivering this message to the intended
recipient:(a)any dissemination or copying of this message is strictly
prohibited; and(b)immediately notify the sender by return message and destroy
any copies of this message in any form(electronic, paper or otherwise) that you
have.The delivery of this message and its information is neither intended to be
nor constitutes a disclosure or waiver of any trade secrets, intellectual
property, attorney work product, or attorney-client communications. The
authority of the individual sending this message to legally bind Prodea Systems
is neither apparent nor implied,and must be independently verified.