When one (of 3) configuration servers was down, we repeatedly received the following error:

Thu May 5 06:32:11 [conn52] Assertion failure _created client/connpool.h 50
0x50f09e 0x520131 0x534da2 0x53799c 0x57bdcc 0x631062 0x66432c 0x6761c7 0x57ea3c 0x69ec30 0x2aee6a11a1b5 0x2aee6ab8e36d
/usr/bin/mongos(_ZN5mongo12sayDbContextEPKc+0xae) [0x50f09e]
/usr/bin/mongos(_ZN5mongo8assertedEPKcS1_j+0x111) [0x520131]
/usr/bin/mongos(_ZN5mongo16DBConnectionPool10appendInfoERNS_14BSONObjBuilderE+0x582) [0x534da2]
/usr/bin/mongos(_ZN5mongo9PoolStats3runERKSsRNS_7BSONObjERSsRNS_14BSONObjBuilderEb+0x1c) [0x53799c]
/usr/bin/mongos(_ZN5mongo7Command20runAgainstRegisteredEPKcRNS_7BSONObjERNS_14BSONObjBuilderE+0x67c) [0x57bdcc]
/usr/bin/mongos(_ZN5mongo14SingleStrategy7queryOpERNS_7RequestE+0x262) [0x631062]
/usr/bin/mongos(_ZN5mongo7Request7processEi+0x29c) [0x66432c]
/usr/bin/mongos(_ZN5mongo21ShardedMessageHandler7processERNS_7MessageEPNS_21AbstractMessagingPortEPNS_9LastErrorE+0x77) [0x6761c7]
/usr/bin/mongos(_ZN5mongo3pms9threadRunEPNS_13MessagingPortE+0x34c) [0x57ea3c]
/usr/bin/mongos(thread_proxy+0x80) [0x69ec30]
/lib64/libpthread.so.0 [0x2aee6a11a1b5]
/lib64/libc.so.6(clone+0x6d) [0x2aee6ab8e36d]

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