Direct connect a switch, and huawei router configuration EBGP routing, run after six months, the current error often hold the timer, information is as follows:
The show IP BGP neighbors
BGP neighbor is 10.21.19.185, remote AS 200, 100, local AS external link
BGP version 4, remote router ID 11.11.11.11
BGP state=Established, up for 00:02:01
The Last read 00:00:17, hold time is 180, keepalive interval is 60 seconds
Neighbor "capabilities:
The Route to refresh: advertised and received (old and new)
The Address family IPv4 Unicast: advertised and received
Received 27 messages, notifications, 0 and queue in
Sent 331 messages, notifications, 20 0 queue in
The Route refresh request: received 0, sent 0
Minimum time between advertisement runs is 30 seconds
For the address family: IPv4 Unicast
BGP table version 21, neighbor version 21

The last reset: 01 w1d23h, due to BGP notification sent
Notification error massage: (Hold the timer Expired/Unspecified error Subcode)