我有一个 xubuntu 盒子，使用它的终端本地一切都很好；但是当我 ssh 到任何服务器时，远程 echo 似乎保留了最后一行直到按下某个键或者窗口大小被调整。在长输出命令中，只输出前几行（即寻找请参阅下面的测试）。该问题不在本地出现，但会影响所有依赖 ssh 的实用程序，即 git、scp。即使进程正在运行并显示输出（除非反复按下键，否则不会更新），ssh 会话也会随机关闭。
在截屏视频中http://www.tmg.it/files/funnyterm.ogv，所有命令都以回车结束；我在命令之间等待 5 秒钟。如您所见，只有当我再次开始输入时，才会显示带有提示符的行。
我进行的测试：
- 从 USB 驱动器上的实时 Ubuntu 13.04 启动显示同样的问题！
- 从 USB 驱动器上的实时 Ubuntu 12.04 启动很好用
- 从 USB 驱动器上的实时 xubuntu 13.04 启动显示同样的问题！
- 无论是使用 WiFi 还是 LAN 连接都会出现同样的问题
- 在窗口中，如果我调整其大小，输出将会更新
- 按右箭头或任何其他非字符键也会更新
- 使用 CTRL-ALT-F1 打开的全屏控制台中也会出现同样的问题
- 使用另一个终端，即 aterm，无法解决问题
- 本地和远程删除 .bashrc 和 .bash_profile 并不能解决问题。
- 该问题出现在几个远程 CentOS 32 位和 64 位 v5.8、5.9 和 6；远程 Ubuntu 10.04.4 LTS 上。
scp 测试：- 如果文件 < MTU，则 scp remotefile localfile 有效。- 尝试摆弄 MTU，将其设置为 1000 至 1600 之间的几个值 - 没有成功。
查找测试：在 ssh 连接中，在包含许多文件的文件夹中查找将在输出几行后停止。按 3-4 次 Return 键将显示接下来的几行。我开始从 iwconfig 监视 Tx 过度重试和无效杂项，并看到“无效杂项”和“过度重试”每返回几次就会增加：
系统是最新的 xubuntu 13.04 amd64，带有 lamp 堆栈，运行在 Samsung RC530-S05IT（i7/6Gb ram/60Gb HDD 分区 + 一个额外的 SSD 驱动器）上。我第一次注意到这个问题是在只安装了 lamp + eclipse 时，并且可以从实时发行版（相同版本）启动时重现它。
网络中的其他系统不会出现此问题（更新！mac 也开始出现此问题！）。在这台电脑上，CentOS 在虚拟机中运行良好，Windows 7 和 Putty 以及 cygwin 也运行良好，此外还有来自 usb/iso 的任何非 13.04 (x)ubuntu 发行版。13.04 (x)ubuntu 甚至无法从实时 usb 启动。
命令输出，iwconfig
$ echo“#在 ssh 连接中查找”；date +“％H：％M：％S”；iwconfig 2> nul | grep misc
#find in ssh connection
14:22:56
Tx excessive retries:695 Invalid misc:273 Missed beacon:0
#find in ssh connection.. after a few returns were pressed in the terminal:
14:23:07
Tx excessive retries:697 Invalid misc:281 Missed beacon:0
$系统配置
eth0 no wireless extensions.
lo no wireless extensions.
wlan0 IEEE 802.11bgn ESSID:"zzz-guests"
Mode:Managed Frequency:2.462 GHz Access Point: A4:B1:E9:97:72:ED
Bit Rate=65 Mb/s Tx-Power=15 dBm
Retry long limit:7 RTS thr:off Fragment thr:off
Power Management:off
Link Quality=62/70 Signal level=-48 dBm
Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:0
Tx excessive retries:582 Invalid misc:209 Missed beacon:0
以下块是在完成巨大的 find 命令后，ubuntu 12.04 上 ssh 工作正常的 iwconfig 的输出：
wlan0 IEEE 802.11bgn ESSID:"zzz-guests"
Mode:Managed Frequency:2.462 GHz Access Point: A4:B1:E9:97:72:ED
Bit Rate=65 Mb/s Tx-Power=15 dBm
Retry long limit:7 RTS thr:off Fragment thr:off
Power Management:off
Link Quality=61/70 Signal level=-49 dBm
Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:0
Tx excessive retries:4 Invalid misc:65 Missed beacon:0
（在这个 12.04 ubuntu 上，lspci 显示与 xubuntu 13.04 加载完全相同的网络驱动程序和版本）
来自我的系统的一些杂项信息
- cat /etc/lsb-release; uname -a
- 请参阅lspci-nnk| grep -iA2 净
- rfkill 列出全部
- 修改
- nm 工具
- lsmod | grep rt2
- sudo cat /var/log/syslog | grep -e rt2 -e firmware -e wpa -e wlan -e etork | tail -n75
$cat /etc/lsb-release; uname -a
DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=13.04
DISTRIB_CODENAME=raring
DISTRIB_DESCRIPTION="Ubuntu 13.04"
Linux osiris 3.8.0-30-generic #44-Ubuntu SMP Thu Aug 22 20:52:24 UTC 2013 x86_64 x86_64 x86_64 GNU/Linux
$请参阅lspci-nnk| grep -iA2 净
02:00.0 Network controller [0280]: Intel Corporation Centrino Wireless-N 130 [8086:0896] (rev 34)
Subsystem: Intel Corporation Centrino Wireless-N 130 BGN [8086:5005]
Kernel driver in use: iwlwifi
03:00.0 Ethernet controller [0200]: Realtek Semiconductor Co., Ltd. RTL8111/8168 PCI Express Gigabit Ethernet controller [10ec:8168] (rev 06)
Subsystem: Samsung Electronics Co Ltd Device [144d:c0c1]
Kernel driver in use: r8169
ric@osiris:~$rfkill 列出全部
0: samsung-wlan: Wireless LAN
Soft blocked: no
Hard blocked: no
...
3: phy0: Wireless LAN
Soft blocked: no
Hard blocked: no
$修改
Module Size Used by
pci_stub 12622 1
vboxpci 23194 0
vboxnetadp 25670 0
vboxnetflt 23479 0
vboxdrv 320372 3 vboxnetadp,vboxnetflt,vboxpci
parport_pc 28152 0
ppdev 17073 0
rfcomm 42641 16
bnep 18036 2
binfmt_misc 17500 1
snd_hda_codec_hdmi 36906 1
snd_hda_codec_realtek 78399 1
joydev 17377 0
arc4 12615 2
snd_hda_intel 39619 3
snd_hda_codec 136498 3 snd_hda_codec_realtek,snd_hda_codec_hdmi,snd_hda_intel
iwldvm 241872 0
mac80211 606457 1 iwldvm
snd_hwdep 13602 1 snd_hda_codec
snd_pcm 97451 3 snd_hda_codec_hdmi,snd_hda_codec,snd_hda_intel
snd_page_alloc 18710 2 snd_pcm,snd_hda_intel
coretemp 13355 0
snd_seq_midi 13324 0
snd_seq_midi_event 14899 1 snd_seq_midi
kvm_intel 132891 0
kvm 443165 1 kvm_intel
snd_rawmidi 30180 1 snd_seq_midi
i915 600349 3
uvcvideo 80847 0
snd_seq 61554 2 snd_seq_midi_event,snd_seq_midi
videobuf2_vmalloc 13056 1 uvcvideo
nouveau 943184 0
ghash_clmulni_intel 13259 0
aesni_intel 55399 1
snd_seq_device 14497 3 snd_seq,snd_rawmidi,snd_seq_midi
videobuf2_memops 13202 1 videobuf2_vmalloc
ttm 83187 1 nouveau
aes_x86_64 17255 1 aesni_intel
drm_kms_helper 49394 2 i915,nouveau
xts 12885 1 aesni_intel
lrw 13257 1 aesni_intel
snd_timer 29425 2 snd_pcm,snd_seq
gf128mul 14951 2 lrw,xts
videobuf2_core 40513 1 uvcvideo
ablk_helper 13597 1 aesni_intel
videodev 129260 2 uvcvideo,videobuf2_core
iwlwifi 173516 1 iwldvm
btusb 22474 0
cryptd 20373 3 ghash_clmulni_intel,aesni_intel,ablk_helper
lp 17759 0
drm 286028 6 ttm,i915,drm_kms_helper,nouveau
microcode 22881 0
cfg80211 510937 3 iwlwifi,mac80211,iwldvm
psmouse 95905 0
bluetooth 228667 22 bnep,btusb,rfcomm
snd 68876 16 snd_hda_codec_realtek,snd_hwdep,snd_timer,snd_hda_codec_hdmi,snd_pcm,snd_seq,snd_rawmidi,snd_hda_codec,snd_hda_intel,snd_seq_device
samsung_laptop 14532 0
serio_raw 13215 0
mei 41158 0
parport 46345 3 lp,ppdev,parport_pc
video 19390 3 i915,samsung_laptop,nouveau
mxm_wmi 13021 1 nouveau
wmi 19070 2 mxm_wmi,nouveau
i2c_algo_bit 13413 2 i915,nouveau
mac_hid 13205 0
lpc_ich 17061 0
soundcore 12680 1 snd
hid_generic 12540 0
usbhid 47074 0
hid 101002 2 hid_generic,usbhid
r8169 67466 0
ahci 25731 5
libahci 31364 1 ahci
$nm 工具
NetworkManager Tool
State: connected (global)
- Device: wlan0 [zzz-guests] --------------------------------------------------
Type: 802.11 WiFi
Driver: iwlwifi
State: connected
Default: yes
HW Address: DC:A9:71:96:81:92
Capabilities:
Speed: 65 Mb/s
Wireless Properties
WEP Encryption: yes
WPA Encryption: yes
WPA2 Encryption: yes
Wireless Access Points (* = current AP)
zzz: Infra, 00:1B:2F:94:ED:BE, Freq 2427 MHz, Rate 54 Mb/s, Strength 99 WPA WPA2
*zzz-guests: Infra, A4:B1:E9:97:72:ED, Freq 2462 MHz, Rate 54 Mb/s, Strength 72 WPA WPA2
IPv4 Settings:
Address: 192.168.1.64
Prefix: 24 (255.255.255.0)sudo cat /var/log/syslog | grep -e rt2 -e firmware -e wpa -e wlan -e etork | tail -n75
Gateway: 192.168.1.254
DNS: 192.168.1.254
$ sudo cat/var/log/syslog| grep -e rt2 -e 固件 -e wpa -e wlan -e etork | tail -n75
Sep 7 14:04:26 osiris NetworkManager[1281]: <info> (wlan0): device state change: secondaries -> activated (reason 'none') [90 100 0]
Sep 7 14:04:26 osiris NetworkManager[1281]: <info> Policy set 'zzz-guests' (wlan0) as default for IPv4 routing and DNS.
Sep 7 14:04:28 osiris NetworkManager[1281]: <info> Activation (wlan0) successful, device activated.
Sep 7 14:04:44 osiris NetworkManager[1281]: <info> (wlan0): IP6 addrconf timed out or failed.
Sep 7 14:04:44 osiris NetworkManager[1281]: <info> Activation (wlan0) Stage 4 of 5 (IPv6 Configure Timeout) scheduled...
Sep 7 14:04:44 osiris NetworkManager[1281]: <info> Activation (wlan0) Stage 4 of 5 (IPv6 Configure Timeout) started...
Sep 7 14:04:44 osiris NetworkManager[1281]: <info> Activation (wlan0) Stage 4 of 5 (IPv6 Configure Timeout) complete.
Sep 7 14:04:58 osiris wpa_supplicant[1376]: wlan0: WPA: Group rekeying completed with a4:b1:e9:97:72:ed [GTK=TKIP]
Sep 7 14:11:37 osiris wpa_supplicant[1376]: dbus: wpa_dbus_get_object_properties: failed to get object properties: (org.freedesktop.DBus.Error.Failed) failed to parse WPA IE
Sep 7 14:11:37 osiris wpa_supplicant[1376]: dbus: Failed to construct signal
Sep 7 14:14:58 osiris wpa_supplicant[1376]: wlan0: WPA: Group rekeying completed with a4:b1:e9:97:72:ed [GTK=TKIP]
Sep 7 14:17:37 osiris wpa_supplicant[1376]: dbus: wpa_dbus_get_object_properties: failed to get object properties: (org.freedesktop.DBus.Error.Failed) failed to parse WPA IE
Sep 7 14:17:37 osiris wpa_supplicant[1376]: dbus: Failed to construct signal
Sep 7 14:24:57 osiris wpa_supplicant[1376]: wlan0: WPA: Group rekeying completed with a4:b1:e9:97:72:ed [GTK=TKIP]
命令输出，stty
这里是 stty -a 的输出，包括本地和 ssh 到远程服务器之后的输出，两者都在 xubuntu 13.04（ssh 有问题）和 ubuntu 12.04 live（可以正常工作）中：
本地控制台（xubuntu 13.04）：
$ stty -a
speed 38400 baud; rows 24; columns 80; line = 0;
intr = ^C; quit = ^\; erase = ^?; kill = ^U; eof = ^D; eol = M-^?; eol2 = M-^?;
swtch = M-^?; start = ^Q; stop = ^S; susp = ^Z; rprnt = ^R; werase = ^W;
lnext = ^V; flush = ^O; min = 1; time = 0;
-parenb -parodd cs8 hupcl -cstopb cread -clocal -crtscts
-ignbrk brkint -ignpar -parmrk -inpck -istrip -inlcr -igncr icrnl ixon -ixoff
-iuclc ixany imaxbel iutf8
opost -olcuc -ocrnl onlcr -onocr -onlret -ofill -ofdel nl0 cr0 tab0 bs0 vt0 ff0
isig icanon iexten echo echoe echok -echonl -noflsh -xcase -tostop -echoprt
echoctl echoke
从 xubuntu 13.04 通过 ssh 连接到远程服务器（centos 5.9）：
$ stty -a
speed 38400 baud; rows 24; columns 80; line = 0;
intr = ^C; quit = ^\; erase = ^?; kill = ^U; eof = ^D; eol = <undef>;
eol2 = <undef>; swtch = <undef>; start = ^Q; stop = ^S; susp = ^Z; rprnt = ^R;
werase = ^W; lnext = ^V; flush = ^O; min = 1; time = 0;
-parenb -parodd cs8 -hupcl -cstopb cread -clocal -crtscts -cdtrdsr
-ignbrk -brkint -ignpar -parmrk -inpck -istrip -inlcr -igncr icrnl ixon -ixoff
-iuclc -ixany -imaxbel -iutf8
opost -olcuc -ocrnl onlcr -onocr -onlret -ofill -ofdel nl0 cr0 tab0 bs0 vt0 ff0
isig icanon iexten echo echoe echok -echonl -noflsh -xcase -tostop -echoprt
echoctl echoke
从 xubuntu 13.04 通过 ssh 连接到不同的服务器（ubuntu 10）：
$ stty -a
speed 38400 baud; rows 24; columns 80; line = 0;
intr = ^C; quit = ^\; erase = ^?; kill = ^U; eof = ^D; eol = M-^?; eol2 = M-^?;
swtch = <undef>; start = ^Q; stop = ^S; susp = ^Z; rprnt = ^R; werase = ^W;
lnext = ^V; flush = ^O; min = 1; time = 0;
-parenb -parodd cs8 -hupcl -cstopb cread -clocal -crtscts
-ignbrk -brkint -ignpar -parmrk -inpck -istrip -inlcr -igncr icrnl ixon -ixoff
-iuclc ixany imaxbel -iutf8
opost -olcuc -ocrnl onlcr -onocr -onlret -ofill -ofdel nl0 cr0 tab0 bs0 vt0 ff0
Ubuntu 12.04.2 LTS 上的本地控制台：
$ stty -a
speed 38400 baud; rows 24; columns 80; line = 0;
intr = ^C; quit = ^\; erase = ^?; kill = ^U; eof = ^D; eol = M-^?; eol2 = M-^?;
swtch = M-^?; start = ^Q; stop = ^S; susp = ^Z; rprnt = ^R; werase = ^W;
lnext = ^V; flush = ^O; min = 1; time = 0;
-parenb -parodd cs8 hupcl -cstopb cread -clocal -crtscts
-ignbrk brkint -ignpar -parmrk -inpck -istrip -inlcr -igncr icrnl ixon -ixoff
-iuclc ixany imaxbel iutf8
opost -olcuc -ocrnl onlcr -onocr -onlret -ofill -ofdel nl0 cr0 tab0 bs0 vt0 ff0
isig icanon iexten echo echoe echok -echonl -noflsh -xcase -tostop -echoprt
echoctl echoke
来自 ubuntu 12.04.2 的远程服务器（centos 5.9）
$ stty -a
speed 38400 baud; rows 24; columns 80; line = 0;
intr = ^C; quit = ^\; erase = ^?; kill = ^U; eof = ^D; eol = <undef>;
eol2 = <undef>; swtch = <undef>; start = ^Q; stop = ^S; susp = ^Z; rprnt = ^R;
werase = ^W; lnext = ^V; flush = ^O; min = 1; time = 0;
-parenb -parodd cs8 -hupcl -cstopb cread -clocal -crtscts -cdtrdsr
-ignbrk -brkint -ignpar -parmrk -inpck -istrip -inlcr -igncr icrnl ixon -ixoff
-iuclc -ixany -imaxbel -iutf8
opost -olcuc -ocrnl onlcr -onocr -onlret -ofill -ofdel nl0 cr0 tab0 bs0 vt0 ff0
isig icanon iexten echo echoe echok -echonl -noflsh -xcase -tostop -echoprt
Windows 7 上的 cygwin ssh -> centos 5.9
$ stty -a
speed 38400 baud; rows 24; columns 100; line = 0;
intr = ^C; quit = ^\; erase = ^?; kill = ^U; eof = ^D; eol = <undef>; eol2 = <undef>;
swtch = <undef>; start = ^Q; stop = ^S; susp = ^Z; rprnt = ^R; werase = ^W; lnext = ^V; flush = ^O;
min = 1; time = 0;
-parenb -parodd cs8 -hupcl -cstopb cread -clocal -crtscts -cdtrdsr
-ignbrk -brkint -ignpar -parmrk -inpck -istrip -inlcr -igncr icrnl ixon -ixoff -iuclc -ixany -imaxbel
-iutf8
opost -olcuc -ocrnl onlcr -onocr -onlret -ofill -ofdel nl0 cr0 tab0 bs0 vt0 ff0
isig icanon iexten echo echoe echok -echonl -noflsh -xcase -tostop -echoprt echoctl echoke
Mac OS X 10.6.8
lflags: icanon isig iexten echo echoe -echok echoke -echonl echoctl
-echoprt -altwerase -noflsh -tostop -flusho pendin -nokerninfo
-extproc
iflags: -istrip icrnl -inlcr -igncr ixon -ixoff ixany imaxbel iutf8
-ignbrk brkint -inpck -ignpar -parmrk
oflags: opost onlcr -oxtabs -onocr -onlret
cflags: cread cs8 -parenb -parodd hupcl -clocal -cstopb -crtscts -dsrflow
-dtrflow -mdmbuf
cchars: discard = ^O; dsusp = ^Y; eof = ^D; eol = <undef>;
eol2 = <undef>; erase = ^?; intr = ^C; kill = ^U; lnext = ^V;
min = 1; quit = ^\; reprint = ^R; start = ^Q; status = ^T;
stop = ^S; susp = ^Z; time = 0; werase = ^W;
12.04 ssh 到 centos 5.9
stty -g
500:5:bf:8a3b:3:1c:7f:15:4:0:1:0:11:13:1a:0:12:f:17:16:0:0:0:0:0:0:0:0:0:0:0:0:0:0:0:0
13.04 ssh 到 centos 5.9
stty -g
500:5:bf:8a3b:3:1c:7f:15:4:0:1:0:11:13:1a:0:12:f:17:16:0:0:0:0:0:0:0:0:0:0:0:0:0:0:0:0
（stty -g 输出相同）
（这个问题最初是在https://superuser.com/questions/640348/xubuntu-xterm-lag-echo-issue-with-ssh）
答案1
关于诊断的更多想法：
分析 stty -a 的输出（已完成，确定排除，见下文讨论）
尝试使用其他网络设备访问网络。您是否遇到过同样的问题
- 无线的
- 以太网
- usb-to-ethernet，或者 usb-to-wlan 适配器？
从 USB 启动另一个（非 Ubuntu）系统
你提到的 scp 测试会让我首先尝试 (2)。
答案2
我也遇到了同样的问题，但在我看来这是一个图形问题。将另一个窗口（部分）移到 xterm 窗口上会使 xterm 窗口刷新并显示丢失的行。有时还会显示一行的一半高度（字符的下半部分不显示）...