ssh command not worked. (It worked about 1 month ago on vpp-18.04)

ping command not worked too.

Scheme PC-VPP-PC:

• PC (192.168.1.100) <outside> (TenGigabitEthernet3/0/0)VPP(GigabitEthernet5/0/1) <inside> PC (192.168.0.100) 

DBGvpp# set interface ip address GigabitEthernet5/0/1 192.168.0.1/24
DBGvpp# set interface ip address TenGigabitEthernet3/0/0 192.168.1.1/24
DBGvpp# set interface state GigabitEthernet5/0/1 up
DBGvpp# set interface state TenGigabitEthernet3/0/0 up
DBGvpp# nat44 add interface address TenGigabitEthernet3/0/0
DBGvpp# set interface nat44 in GigabitEthernet5/0/1 out TenGigabitEthernet3/0/0 output-feature
DBGvpp#
DBGvpp#
DBGvpp# nat44 forwarding enable
DBGvpp#
DBGvpp# trace add dpdk-input 10
DBGvpp#

192.168.1.100# ssh 192.168.1.1 <<< DON'T WORK**

DBGvpp# show trace
------------------- Start of thread 0 vpp_main -------------------
Packet 1

00:08:51:972548: dpdk-input
TenGigabitEthernet3/0/0 rx queue 0
buffer 0xe9bd: current data 14, length 60, free-list 0, clone-count 0, totlen-nifb 0, trace 0x0
ext-hdr-valid
l4-cksum-computed l4-cksum-correct l2-hdr-offset 0
PKT MBUF: port 0, nb_segs 1, pkt_len 74
buf_len 2176, data_len 74, ol_flags 0x180, data_off 128, phys_addr 0x6e5a6fc0
packet_type 0x111 l2_len 0 l3_len 0 outer_l2_len 0 outer_l3_len 0
rss 0x0 fdir.hi 0x0 fdir.lo 0x0
Packet Offload Flags
PKT_RX_IP_CKSUM_GOOD (0x0080) IP cksum of RX pkt. is valid
PKT_RX_L4_CKSUM_GOOD (0x0100) L4 cksum of RX pkt. is valid
Packet Types
RTE_PTYPE_L2_ETHER (0x0001) Ethernet packet
RTE_PTYPE_L3_IPV4 (0x0010) IPv4 packet without extension headers
RTE_PTYPE_L4_TCP (0x0100) TCP packet
IP4: 00:a0:c9:00:00:00 -> ac:1f:6b:8d:01:66
TCP: 192.168.1.100 -> 192.168.1.1
tos 0x00, ttl 64, length 60, checksum 0x5887
fragment id 0x5e7f, flags DONT_FRAGMENT
TCP: 47820 -> 22
seq. 0x4919a8fe ack 0x00000000
flags 0x02 SYN, tcp header: 40 bytes
window 29200, checksum 0xa4cc
00:08:51:972567: ip4-input-no-checksum
TCP: 192.168.1.100 -> 192.168.1.1
tos 0x00, ttl 64, length 60, checksum 0x5887
fragment id 0x5e7f, flags DONT_FRAGMENT
TCP: 47820 -> 22
seq. 0x4919a8fe ack 0x00000000
flags 0x02 SYN, tcp header: 40 bytes
window 29200, checksum 0xa4cc
00:08:51:972583: nat44-out2in
NAT44_OUT2IN: sw_if_index 1, next index 1, session index 0
00:08:51:972592: ip4-lookup
fib 0 dpo-idx 0 flow hash: 0x00000000
TCP: 192.168.1.100 -> 124.0.0.0
tos 0x00, ttl 64, length 60, checksum 0x9e30
fragment id 0x5e7f, flags DONT_FRAGMENT
TCP: 47820 -> 0
seq. 0x4919a8fe ack 0x00000000
flags 0x02 SYN, tcp header: 40 bytes
window 29200, checksum 0xea8b
00:08:51:972599: ip4-drop
TCP: 192.168.1.100 -> 124.0.0.0
tos 0x00, ttl 64, length 60, checksum 0x9e30
fragment id 0x5e7f, flags DONT_FRAGMENT
TCP: 47820 -> 0
seq. 0x4919a8fe ack 0x00000000
flags 0x02 SYN, tcp header: 40 bytes
window 29200, checksum 0xea8b
00:08:51:972602: error-drop
dpdk-input: no error

DBGvpp# clear trace

192.168.1.100# ping 192.168.1.1 <<< DON'T WORK

 DBGvpp# trace add dpdk-input 10
DBGvpp# show trace
------------------- Start of thread 0 vpp_main -------------------
Packet 1

00:35:59:152312: dpdk-input
TenGigabitEthernet3/0/0 rx queue 0
buffer 0xe810: current data 14, length 84, free-list 0, clone-count 0, totlen-nifb 0, trace 0x0
ext-hdr-valid
l4-cksum-computed l4-cksum-correct l2-hdr-offset 0
PKT MBUF: port 0, nb_segs 1, pkt_len 98
buf_len 2176, data_len 98, ol_flags 0x180, data_off 128, phys_addr 0x6e5a0480
packet_type 0x11 l2_len 0 l3_len 0 outer_l2_len 0 outer_l3_len 0
rss 0x0 fdir.hi 0x0 fdir.lo 0x0
Packet Offload Flags
PKT_RX_IP_CKSUM_GOOD (0x0080) IP cksum of RX pkt. is valid
PKT_RX_L4_CKSUM_GOOD (0x0100) L4 cksum of RX pkt. is valid
Packet Types
RTE_PTYPE_L2_ETHER (0x0001) Ethernet packet
RTE_PTYPE_L3_IPV4 (0x0010) IPv4 packet without extension headers
IP4: 00:a0:c9:00:00:00 -> ac:1f:6b:8d:01:66
ICMP: 192.168.1.100 -> 192.168.1.1
tos 0x00, ttl 64, length 84, checksum 0xe5a7
fragment id 0xd14b, flags DONT_FRAGMENT
ICMP echo_request checksum 0xd3b8
00:35:59:152332: ip4-input-no-checksum
ICMP: 192.168.1.100 -> 192.168.1.1
tos 0x00, ttl 64, length 84, checksum 0xe5a7
fragment id 0xd14b, flags DONT_FRAGMENT
ICMP echo_request checksum 0xd3b8
00:35:59:152349: nat44-out2in
NAT44_OUT2IN: sw_if_index 1, next index 1, session index -1
00:35:59:152357: ip4-lookup
fib 0 dpo-idx 6 flow hash: 0x00000000
ICMP: 192.168.1.100 -> 192.168.1.1
tos 0x00, ttl 64, length 84, checksum 0xe5a7
fragment id 0xd14b, flags DONT_FRAGMENT
ICMP echo_request checksum 0xd3b8
00:35:59:152364: ip4-local
ICMP: 192.168.1.100 -> 192.168.1.1
tos 0x00, ttl 64, length 84, checksum 0xe5a7
fragment id 0xd14b, flags DONT_FRAGMENT
ICMP echo_request checksum 0xd3b8
00:35:59:152368: ip4-icmp-input
ICMP: 192.168.1.100 -> 192.168.1.1
tos 0x00, ttl 64, length 84, checksum 0xe5a7
fragment id 0xd14b, flags DONT_FRAGMENT
ICMP echo_request checksum 0xd3b8
00:35:59:152378: ip4-icmp-echo-request
ICMP: 192.168.1.100 -> 192.168.1.1
tos 0x00, ttl 64, length 84, checksum 0xe5a7
fragment id 0xd14b, flags DONT_FRAGMENT
ICMP echo_request checksum 0xd3b8
00:35:59:152382: ip4-load-balance
fib 0 dpo-idx 17 flow hash: 0x00000000
ICMP: 192.168.1.1 -> 192.168.1.100
tos 0x00, ttl 64, length 84, checksum 0x54ce
fragment id 0x6225, flags DONT_FRAGMENT
ICMP echo_reply checksum 0xdbb8
00:35:59:152385: ip4-rewrite
tx_sw_if_index 1 dpo-idx 2 : ipv4 via 192.168.1.100 TenGigabitEthernet3/0/0: mtu:9000 00a0c9000000ac1f6b8d01660800 flow hash: 0x00000000
00000000: 00a0c9000000ac1f6b8d016608004500005462254000400154cec0a80101c0a8
00000020: 01640000dbb80a18000256d4515b00000000ae2a0500000000001011
00:35:59:152389: nat44-in2out-output
NAT44_IN2OUT_FAST_PATH: sw_if_index 0, next index 3, session -1
00:35:59:152395: nat44-in2out-output-slowpath
NAT44_IN2OUT_SLOW_PATH: sw_if_index 0, next index 0, session 1
00:35:59:152403: TenGigabitEthernet3/0/0-output
TenGigabitEthernet3/0/0
IP4: ac:1f:6b:8d:01:66 -> 00:a0:c9:00:00:00
ICMP: 192.168.1.1 -> 192.168.1.100
tos 0x00, ttl 64, length 84, checksum 0x54ce
fragment id 0x6225, flags DONT_FRAGMENT
ICMP echo_reply checksum 0xa653
00:35:59:152409: TenGigabitEthernet3/0/0-tx
TenGigabitEthernet3/0/0 tx queue 0
buffer 0xe810: current data 0, length 98, free-list 0, clone-count 0, totlen-nifb 0, trace 0x0
ext-hdr-valid
l4-cksum-computed l4-cksum-correct l2-hdr-offset 0
PKT MBUF: port 0, nb_segs 1, pkt_len 98
buf_len 2176, data_len 98, ol_flags 0x180, data_off 128, phys_addr 0x6e5a0480
packet_type 0x11 l2_len 0 l3_len 0 outer_l2_len 0 outer_l3_len 0
rss 0x0 fdir.hi 0x0 fdir.lo 0x0
Packet Offload Flags
PKT_RX_IP_CKSUM_GOOD (0x0080) IP cksum of RX pkt. is valid
PKT_RX_L4_CKSUM_GOOD (0x0100) L4 cksum of RX pkt. is valid
Packet Types
RTE_PTYPE_L2_ETHER (0x0001) Ethernet packet
RTE_PTYPE_L3_IPV4 (0x0010) IPv4 packet without extension headers
IP4: ac:1f:6b:8d:01:66 -> 00:a0:c9:00:00:00
ICMP: 192.168.1.1 -> 192.168.1.100
tos 0x00, ttl 64, length 84, checksum 0x54ce
fragment id 0x6225, flags DONT_FRAGMENT
ICMP echo_reply checksum 0xa653

DBGvpp# show nat44 sessions details
NAT44 sessions:
-------- thread 0 vpp_main --------
124.0.0.0: 0 dynamic translations, 1 static translations
i2o 124.0.0.0 proto tcp port 0 fib 0
o2i 192.168.1.1 proto tcp port 22 fib 0
index 0
last heard 595.77
total pkts 12, total bytes 720
static translation

192.168.1.1: 1 dynamic translations, 0 static translations
i2o 192.168.1.1 proto icmp port 2584 fib 0
o2i 192.168.1.1 proto icmp port 16253 fib 0
index 1
last heard 2309.45
total pkts 152, total bytes 14896
dynamic translation