redis-cluster error on bgsave

[shcherbak]

the same error reproduces on another slave. after restart (see stack trace below) slave can't connect to master. it is odd because master is available:

29189:S 29 Mar 20:01:11.181 * Connecting to MASTER ?:6379 29189:S 29 Mar 20:01:11.183 # Unable to connect to MASTER: Resource temporarily unavailable 29189:S 29 Mar 20:01:11.297 - Accepted 192.168.210.44:21596 29189:S 29 Mar 20:01:11.300 - Client closed connection
syslog:
Mar 29 19:28:22 bo-redis-cluster-07 kernel: [1133085.729815] redis-server[11177]: segfault at 36353334cd ip 000055e1c790ff64 sp 00007fff0be12cf0 error 4 in redis-server[55
e1c78d9000+e5000]

stack trace:
`11177:S 29 Mar 19:27:12.347 * MASTER <-> SLAVE sync: Flushing old data

=== REDIS BUG REPORT START: Cut & paste starting from here ===
11177:S 29 Mar 19:28:22.958 # Redis 3.2.8 crashed by signal: 11
11177:S 29 Mar 19:28:22.958 # Crashed running the instuction at: 0x55e1c7907105
11177:S 29 Mar 19:28:22.958 # Accessing address: 0xaca40
11177:S 29 Mar 19:28:22.958 # Failed assertion: (:0)

------ STACK TRACE ------
EIP:
/usr/bin/redis-server 0.0.0.0:6379 cluster[0x55e1c7907105]

Backtrace:
/usr/bin/redis-server 0.0.0.0:6379 cluster[0x55e1c793f105]
/usr/bin/redis-server 0.0.0.0:6379 cluster[0x55e1c793f8d0]
/lib/x86_64-linux-gnu/libpthread.so.0(+0xf890)[0x7f6a3d85a890]
/usr/bin/redis-server 0.0.0.0:6379 cluster[0x55e1c7907105]
/usr/bin/redis-server 0.0.0.0:6379 cluster[0x55e1c78fe43a]
/usr/bin/redis-server 0.0.0.0:6379 cluster[0x55e1c78fee48]
/usr/bin/redis-server 0.0.0.0:6379 cluster[0x55e1c7918a6a]
/usr/bin/redis-server 0.0.0.0:6379 cluster[0x55e1c791a37a]
/usr/bin/redis-server 0.0.0.0:6379 cluster[0x55e1c78fc0a7]
/usr/bin/redis-server 0.0.0.0:6379 cluster[0x55e1c78fc42b]
/usr/bin/redis-server 0.0.0.0:6379 cluster[0x55e1c78f92a4]
/lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xf5)[0x7f6a3d4c1b45]
/usr/bin/redis-server 0.0.0.0:6379 cluster[0x55e1c78f9459]

------ INFO OUTPUT ------

Server

redis_version:3.2.8
redis_git_sha1:00000000
redis_git_dirty:0
redis_build_id:bb0ba4e36835f109
redis_mode:cluster
os:Linux 4.9.0-0.bpo.5-amd64 x86_64
arch_bits:64
multiplexing_api:epoll
gcc_version:4.9.2
process_id:11177
run_id:78c1bf581dae64cef3d4772f3970ca24d03e78b2
tcp_port:6379
uptime_in_seconds:181820
uptime_in_days:2
hz:10
lru_clock:12394990
executable:/usr/bin/redis-server
config_file:/etc/redis/redis.conf

Clients

connected_clients:661
client_longest_output_list:0
client_biggest_input_buf:0
blocked_clients:0

Memory

used_memory:21849073336
used_memory_human:20.35G
used_memory_rss:26176933888
used_memory_rss_human:24.38G
used_memory_peak:26410795144
used_memory_peak_human:24.60G
total_system_memory:50654183424
total_system_memory_human:47.18G
used_memory_lua:37888
used_memory_lua_human:37.00K
maxmemory:36507222016
maxmemory_human:34.00G
maxmemory_policy:volatile-lru
mem_fragmentation_ratio:1.20
mem_allocator:jemalloc-3.6.0

Persistence

loading:0
rdb_changes_since_last_save:0
rdb_bgsave_in_progress:0
rdb_last_save_time:1522338127
rdb_last_bgsave_status:ok
rdb_last_bgsave_time_sec:278
rdb_current_bgsave_time_sec:-1
aof_enabled:0
aof_rewrite_in_progress:0
aof_rewrite_scheduled:0
aof_last_rewrite_time_sec:-1
aof_current_rewrite_time_sec:-1
aof_last_bgrewrite_status:ok
aof_last_write_status:ok

Stats

total_connections_received:710503
total_commands_processed:98159145
instantaneous_ops_per_sec:5
total_net_input_bytes:68654399368
total_net_output_bytes:15649898860
instantaneous_input_kbps:203063.88
instantaneous_output_kbps:50.51
rejected_connections:0
sync_full:2
sync_partial_ok:1
sync_partial_err:0
expired_keys:0
evicted_keys:0
keyspace_hits:0
keyspace_misses:0
pubsub_channels:0
pubsub_patterns:0
latest_fork_usec:844704
migrate_cached_sockets:0

Replication

role:slave
master_host:192.168.210.25
master_port:6379
master_link_status:down
master_last_io_seconds_ago:-1
master_sync_in_progress:1
slave_repl_offset:1
master_sync_left_bytes:0
master_sync_last_io_seconds_ago:0
master_link_down_since_seconds:615
slave_priority:100
slave_read_only:1
connected_slaves:0
master_repl_offset:0
repl_backlog_active:0
repl_backlog_size:1048576
repl_backlog_first_byte_offset:135444
repl_backlog_histlen:9226

CPU

used_cpu_sys:7513.40
used_cpu_user:21987.21
used_cpu_sys_children:816.94
used_cpu_user_children:9081.84

Commandstats

cmdstat_set:calls=6108441,usec=133729901,usec_per_call=21.89
cmdstat_setex:calls=80808830,usec=2117203889,usec_per_call=26.20
cmdstat_del:calls=5107658,usec=592890065,usec_per_call=116.08
cmdstat_hset:calls=246,usec=28956,usec_per_call=117.71
cmdstat_mset:calls=5455124,usec=125112351,usec_per_call=22.93
cmdstat_select:calls=2,usec=5,usec_per_call=2.50
cmdstat_ping:calls=16281,usec=10617,usec_per_call=0.65
cmdstat_psync:calls=3,usec=1227507,usec_per_call=409169.00
cmdstat_replconf:calls=2715,usec=8749,usec_per_call=3.22
cmdstat_info:calls=3027,usec=1872865,usec_per_call=618.72
cmdstat_config:calls=3017,usec=104086,usec_per_call=34.50
cmdstat_cluster:calls=591767,usec=242106073,usec_per_call=409.12
cmdstat_client:calls=62034,usec=226240,usec_per_call=3.65

Cluster

cluster_enabled:1

Keyspace

db0:keys=55303769,expires=63518939,avg_ttl=1112813656
hash_init_value: 1521491131

------ CLIENT LIST OUTPUT ------
29189:M 29 Mar 19:28:25.976 * Node configuration loaded, I'm d1292e9823883bfa8bbc058f110480f9cdb2c098
.
.-__ ''-._ _.- . . ''-._ Redis 3.2.8 (00000000/0) 64 bit
.- .-```. ```\/ _.,_ ''-._ ( ' , .-` | `, ) Running in cluster mode |`-._`-...-` __...-.-.|'_.-'| Port: 6379 | -. ._ / _.-' | PID: 29189 -._ -._ -./ .-' .-'
|-._-. -.__.-' _.-'_.-'| | -.-._ _.-'_.-' | http://redis.io -._ -._-..-'.-' .-'
|-._-. -.__.-' _.-'_.-'| | -.-._ _.-'_.-' | -._ -._-..-'_.-' _.-'
-._ -..-' _.-'
-._ _.-' -..-'

29189:M 29 Mar 19:28:25.977 # Server started, Redis version 3.2.8`